# why does the equation x^2=-9 has no real solution why does the equation x^2 = 9 has two solutions

56,329 questions, page 242
1. ## Chemistry

Which statement about this reaction is FALSE? AgNO3 + NaCl -> AgCl + NaNO3 A. This is one kind of metathesis reaction, where molecules exchange atoms. B. This reaction produces a gas. C. This is a precipitation reaction. D. The equation is balanced

asked by Anonymous on April 17, 2017
2. ## math

The mass m(t) remaining after t days from a 70 g sample of thorium-234 is given by the equation shown below. m(t) = 70e-0.0274t Find the half-life of thorium-234. (Round your answer to the nearest tenth.)

asked by Anonymous on March 13, 2010
3. ## physics

Starting from rest, a 93-kg firefighter slides down a fire pole. The average frictional force everted on him by the pole has a magnitude of 710 N, and his speed at the bottom of the pole is 3.2 m/s. How far did he slide down the pole? What equation do you

asked by BrookeNeed on October 14, 2016
4. ## Algebra

How do you a write an equation that shows this relationship a cell phone company offers a plan which includes unlimited texting for $40 per month and 250 anytime minutes per month, plus$0.20 for each minute over 250.

asked by Anonymous on August 1, 2016
5. ## CHEMISTRY

Hello, I am trying to balance this redox reaction WITHOUT using the half-reaction method. Here is the unbalanced equation: MnO4 -(aq) + Zn(s)--> Mn 2+(aq) + Zn 2+(aq) It looks as if both elements are being oxidized. The answer is supposed to be: 2MnO4

asked by Vanessa on April 22, 2010
6. ## Math

Gina works at a diner. She earns $6 each hour plus tips. In one week, she worked 37 hours a week and earned$43 in tips. How much did she make altogether? Write an equation. Use a variable for the unknown. Solve

asked by Miley on November 30, 2015

The cost of a student ticket to the school play is $7. Write an equation that correctly relates the total cost, c, for a particular number, s, of student tickets purchased. Identify the independent and dependent variables. asked by connexus guy. on March 27, 2018 8. ## Chemistry AgNO3 + NaCl -> AgCl + NaNO3 Which statement about this reaction is FALSE? A. This is one kind of metathesis reaction, where molecules exchange atoms. B. This reaction produces a gas. C. This is a precipitation reaction. D. The equation is balanced. asked by Riley on April 17, 2017 9. ## Algebra For this question I answered part A. But I am lost on what I am suppose to do for question B. Given d varies jointly as r and the square of s and inversely as t and d =8 when r=3, s=2, and t=6. A. What is the constant of proportionality? Show your work. asked by Ebony on February 16, 2017 10. ## algebra angela ate at the same restaurant four times each time she ate a salad and left a 5 dollar tip she spent a total of 54 dollars write and solve an equation to find the cost of each salad asked by drew decker on October 19, 2011 11. ## Chemistry :) Balance the following redox equation and identify the element oxidized, the element reduced, the oxidizing agent, and the reducing agent. Show all of the work used to solve the problem. NO2- + Al AlO2- + NH3 Thanks :) asked by Julia on June 19, 2011 12. ## math The cost of a student ticket to the school play is$7. Write an equation that correctly relates the total cost, c, for a particular number, s, of student tickets purchased. Identify the independent and dependent variables.

asked by Anonymous on May 24, 2016

Given the following equation, C3H8 (g) + 5O2 (g) -> 3CO2 (g) + 4H2O (g); H comb = -2219 kJ/mole A) how much heat will be released when 10 g of propane is burned? B) how much heat will be released when 10 g of water (H2O) is formed? Please show all work.

asked by Lassie on May 8, 2012
14. ## Physics

A copper wire with a length 2.0m, cross sectional area 7.1x10^-6 m^2 and young's modulus 11x10^10 N/m^2 has a 200kg load hung on it. What is its increase the length? (g=9.8 m/s^2) im not sure how to start this problem or what equation to use, can some one

asked by BrOwN GuRL on November 11, 2007
15. ## Math

Gina works at a diner. She earns $6 each hour plus tips.In one week,she worked 37 hours a week and earned$43 in tips.How much did she make altogether? Write an equation. Use a variable for the unknown.Solve.

asked by Mikaela on December 7, 2016
16. ## Chemistry

Write a balanced equation for the combustion of gaseous ethane (C2H6) a minority component of natural gas, in which it combines with gaseous oxygen to form gaseous carbon dioxide and gaseous water.

asked by Christine on November 6, 2012
17. ## Trigonometry

A weight hanging from the end of a spring is pulled 8 inches below its rest position. When released, the weight then exhibits simple harmonic motion, with period 1/2 second. Find an equation describing its motion

asked by Liv on October 1, 2016

If I had the old-fashion camera that had a focal length of 35mm(0.035m) and I take a picture of a person 6 m away, how far does the film need to be from the lens to record a clear image? I know that the equation is 1/f = 1/d(object) + 1/d(image) so would I

asked by Roberto on February 12, 2011

Hi, a particle is moving in simple harmonic motion such that a = -4x. ( x in metres, t in seconds) Find the maximum speed at which the particle is travelling. Velocity = 6cos2t. My teacher said to put t = 0 and sub it into velocity equation above, but I

asked by Michelle on July 18, 2012
20. ## Chemistry Lab

Determine the ionization energy of a hydrogen atom (in kJ/mol) if the electron is in its ground state. (Hints: Use the Rydberg equation, remember E=hc for a single H atom, and R=109678x10–2nm–1 ) _____ kJ/mol Thanks :)

asked by Shawn Tabrizi on January 17, 2011
21. ## Chemistry

Hydrogen sulfide burns in the presense of oxygen producing sulfiar dioxide and water I got HS + O2 >>> SO2 + H2O Its not balanced yet, but can you check if i wrote the equation right? Does the hydrogen sulfide need charges added to them?

asked by Chopsticks on February 4, 2009
22. ## physics

The rider sees a traffic queue ahead. He applies the brakes and reduces the speed of the motorbike from 18 m/s to 3 m/s. Use the equation in the box to calculate the kinetic energy lost by the motorbike. 1 over 2× mass × speed

asked by joe on February 15, 2012

A company that bought a machine for $30,000 wants to depreciate its entire value equally over the next ten years. Write an equation that represents the machine's value, v, in terms of the number of years that have passed since the machines purchase, t. asked by Haley on November 20, 2013 24. ## Dot product I cant get the correct answer and I can't figure out what I am doing wrong. If a=(2,2k) and b=(4,k) are perpendicular, find k. I have worked it out, and I got -2 but it doesn't work when I check it in the original equation. It should be a.b=0 and then plug asked by Derek on June 30, 2008 25. ## CHEMISTRY.. *What are the products after a single replacement rxn? *Determine the spectator ion(s) and the net ionic equation. F2(g) + AlBr3(aq)--->? After single replacement....Br2 is a liquid, not a solid so ppt will not form..hence, there is no reaction? asked by Anonymous on October 16, 2013 26. ## college physics "The Magnitude of the buoyant force is equal to the weight of fluid displaced” is a statement of which principle in the study of fluids? Select one: a. Pascal's Principle b. Archimedes' Principle c. Bernouilli’s Principle d. The Equation of Continuity asked by allen on June 16, 2014 27. ## Chem what is the heat of reaction when 1 mole of gaseous hexane, c6h14 undergoes combustion as in following equation c6h14+19/2o2=6co2+7h2o a) -5221kj b)-38887kj c)-468.2kj d)+163.2KJ asked by Kaur on June 11, 2014 28. ## Trigonometry/ please help! Assume that simple harmonic motion of a spring is described by the equation S=4 cos πt/ 2 where s is in centimetres and t is in seconds. When during the time 0 asked by Henry on August 29, 2015 29. ## algebra Find the equation of a line that passes through the points (1/3, 2/5) and (–4/5, 1/2). Please put your final answer in standard form (Ax + By = C) and please make sure that there are NO fractions (or decimals) in this answer and that the “x” term is asked by Laura on February 10, 2015 30. ## arithmetic brandy wants to buy a digital camera that costs$300. supposeshe saves $15 each week, in how many weeks will she have enough money for the camera? use a bar diagram to solve arithmetically, then use an equation to solve algebraically asked by Anonymous on March 27, 2018 31. ## Pre-Calculus How do you factor this completly 7x*(4x-5)^3+(4x-5)^4 I am confused by the different power of exponets and the 7x in front Can you please help me? 7x*(4x-5)^3+(4x-5)^4 factor out the common term: (4x-5)^3 * (7x+4x-5) Then simplify the second term. what asked by Jessica on June 28, 2006 32. ## Chemistry For calculating the concentration of a metal Ion in Equilibrium with a complex ion...how do I get the right hand side of this equation to equal 5.9 E -8? x(0.98 + 2x)2 _____________ = 1.7 E 7 (0.010-x) then, x(0.98)2 ________ = 5.9 E -8 0.010 I understand asked by Lisa on March 16, 2013 33. ## maths solve the following by a quadratic equation and then solving it. a rocket is projected vertically upwards from ground level, its height "h" meters. how long does it take to reach 50 meters? you should have two answers, explain the meaning of the two asked by Anonymous on April 30, 2017 34. ## Chemistry Write a balanced equation for the combustion of gaseous ethylene (C2H4), an important natural plant hormone, in which it combines with gaseous oxygen to form gaseous carbon dioxide and gaseous water asked by Samantha on March 31, 2015 35. ## AP Chemistry The rate constant for the equation, 2C2F4 → C4F8, is 0.05 M^−1· s^−1. We start with 0.111 mol C2F4 in a 3.00-liter container, with no C4F8 initially present. What will be the concentration of C2F4 after 1.00 hour? Answer in units of M. asked by David on November 29, 2016 36. ## chemistry For each of the following solutions, calculate the initial pH and the final pH after adding 0.010 mol of HCℓ. a) 500.0 mL of pure water i'm not sure how to do this question.. would the equation be h20+h30 equilibrium arrows h30+h20 asked by help on December 1, 2010 37. ## calcules The price of beef in the United States has been found to depend on the demand (measured by per capita consumption) according to the equation q=342.5/p^0.5314 Find the elasticity. Is the demand for beef elastic or inelastic? asked by Merfit on March 30, 2014 38. ## chemistry To maintain the effectiveness of a buffer, relative concentrations of the acid and the conjugate base should not differ by a factor of 10. Based on this information, derive pH range within which the buffer can work effectively. I know that I have to use asked by Jamie on April 16, 2013 39. ## Chemistry Write the balanced equation for (aq) Pb(ClO3)2 and (aq) NaI. Include phases. What mass of precipitate will form if 1.50 L of concentrated Pb(ClO3)2 is mixed with .250 L of .110 M NaI? Assume the reaction goes to completion. asked by Chelsea on October 4, 2013 40. ## college algebra A circular vent pipe with a diameter of 5.5 inches is place on a roof that has a slope of 1/4. Find an equation of the ellipse that should be cut from the roof so that the pipe will fit. roound parameters to the nearest hundreth. asked by Mark on December 10, 2013 41. ## chemistry To maintain the effectiveness of a buffer, relative concentrations of the acid and the conjugate base should not differ by a factor of 10. Based on this information, derive pH range within which the buffer can work effectively. I know that I have to use asked by Jamie on April 16, 2013 42. ## chem-Am I Right???? For 0.10 M ZnCl2 and 0.10 M KAl(SO4)2, find:? a) spectator ions (if any) b) ions expected to hydrolyze (if any) c) net ionic equation for hydrolysis d) expression for equilibrium constant (Ka or Kb) e) value of Ka or Kb My answers are: a) Cl- ; K+ ; SO4^2- asked by Isabella on October 19, 2010 43. ## physics A particle executes simple harmonic motion with an amplitude of 10 cm and time period 6 s. At t=0 it is at position x=5 cm going towards positive x direction . Write the equation for the displacement x at time t. Find the magnitude of the acceleration of asked by Pronab on November 18, 2010 44. ## chemistry To maintain the effectiveness of a buffer, relative concentrations of the acid and the conjugate base should not differ by a factor of 10. Based on this information, derive pH range within which the buffer can work effectively. I know that I have to use asked by Jamie on April 16, 2013 45. ## Math the cost of a student ticket to the schools play is$7. write an equation that correctly relates the cost,c,for particular number of student tickets,s,purchased indetify the independent and dependent variables (3 Points) Please help

asked by mang on May 11, 2015
46. ## Maths

The taxi fare in a city is such that rs.50 is the fixed amount for the first two kilometers and rs.10 for the subsequent kilometers is charged.Taking the distance covered as " x"km and total fare as rs ." Y" ,write a linear equation in "x" and "y"

asked by Genius on December 4, 2016
47. ## statistics

a fair dice is tossed 100 times. use equation 5.20 to bound the probability that the total number of spots is between 300 and 400 p[Mn-mui= 1- sigma square/n(abselone)square

asked by alvina on December 19, 2010
48. ## Calculus

I don't quite understand how to go about solving these so if you could explain them It would be much appreciated! ^o^ 1. The radius, r, of a sphere is increasing at a constant rate of 0.05 meters per second. A. At the time when the radius of the sphere is

asked by Lata on December 14, 2018
49. ## Science

Hello :) my name is Deqa, i was wondering if anyone knew the affects of a state of a substance on the reaction so generally speaking does it matter if a solid is dissolved in a solution or is it faster for a solution be added to another solution basically

asked by Deqa on March 20, 2007
50. ## Biology

A student wishes to prepare 300 mL of 0.25 M sucrose. He puts 25.7 g of sucrose in a beaker and then adds 300 mL of dH2O. The total volume of the solution after the sucrose has been dissolved is 330 mL. a) What did he do wrong when preparing his solution?

asked by Ki on September 14, 2014
51. ## math

The sum of three consecutive integers is 303. If n is the smallest of the three, which equation represents this situation? 3n = 303 3n + 3 = 303 n3 + 3 = 303 n3 + 3n = 303 Need help with this because I have a test Friday on them.

asked by treshia on February 6, 2014
52. ## CITY SCHOOL

useing these numbers: 25 - 7 - 8 - 5 - 4 - 3 make an equation so that the answer equals 828,but you can ONLY use those numbers. you cant add any more numbers and you cant repeat any of the numbers. you DON'T have to use all the numbers though

53. ## algebra

solve the equation or formula for the indicated variable R=ts^2+3 a)s=under radical R-3/t (not under radical b)s=everything under radical R-3/t c)s=R (under radical)-3/t d)s=everything under radical R/t-3 Thanks again I feel really stupid not being able to

asked by Kandy on August 28, 2014
54. ## sir steve reiny damon bob maths help steve!!!

Point P(2,1) and Q(4,-5) lie on a circle. If line 2x-y-13=0 is a tangent to the circle at Q, what is (*) Coordinates of the center of the circle; (*) Equation of the circle. (*) Sketch out your circle. Step

asked by yourim on April 28, 2017

Posted by Megan on Tuesday, October 12, 2010 at 3:44pm. I have a question if someone could help, please explain it. Given b = -1 and h = -1, what is the equation of the graph if the parent function is y = sqrt (x) Answers: a.y = sqrt(x-1) b.y = sqrt (-x+1)

asked by Megan on October 12, 2010
56. ## Chemistry

How much water would be formed if 3.00 mol NH3 reacted with excess oxygen gas in the following equation? Given the reaction 4NH3+ 5O2 --> 4NO + 6H2O A) 2.00 mol B) 3.00 mol C) 4.50 mol D) 6.00 mol E) None of these

asked by Petey on April 9, 2016
57. ## managerial economics

A company wants to estimate how effective different types of advertising are for promoting its products. Specifically, the company is interested in estimating the effectiveness of radio advertising and newspaper advertising. A sample of 50 cities is

asked by brite on September 4, 2017
58. ## Math

Write Each equation in slope-intercept form then identify the slope and the y-intercept for each line 2x-y=12

asked by Tanya on February 18, 2010
59. ## Math

Hi! I need help with this. Thank you! Directions: Solve this equation by doing it twice; one time using the substitution method and one time using the graphing method. -2/3 x + y = 2 2x – 3y = 6

asked by Steffi on March 3, 2015
60. ## Algebra 2

Write the standard form of the equation of the line through the given point with the given slope. Through point: (1,2) slope=7

asked by SoccerStar on October 9, 2012
61. ## Pre-calculus

Find the equation of the locus of the point which moves so that its distance from the point (2,0) is 2/3 its distance from the line y=5.

asked by Ace on August 31, 2016
62. ## Math - Calculus

Show that the equation log y = 1.54 - .008x - .658 log x is equivalent to y = 34.7 (1.0186)^(-x) * x^(-.658)

asked by Alex on March 10, 2010
63. ## algebra

How do you determine whether/how many nonreal solutions an equation has? The statement: x^3 - 4x^2 - 3x + 2 = 0 has two nonreal solutions is false How do I solve this?

asked by Kim on December 1, 2011
64. ## PRECALCULUS

Solve the equation in the indicated domain. 1. 2cos^2 x-5cos x +2=0 x E[0,360) 2. sin^2 x+5 sin x +6=0 x E[0,360)

asked by Anonymous on November 19, 2013
65. ## Math

For the sequence 0,3,8,15,24; Write the general term (an equation) for the nth term of this sequence I got tn=n^2-1. Is this correct??

asked by Anonymous on May 6, 2018
66. ## Calculus

Let f(x) = \sqrt[3] x. The equation of the tangent line to f(x) at x = 125 is y = Using this, we find our approximation for \sqrt[3] {125.4} is =

asked by Alessandra Romano on October 31, 2014
67. ## Simple equation help

What is the chemical equation for the Steel wool and Vinegar experiment for when the steel wool rusts?

asked by Anonymous on September 22, 2017
68. ## Maths

If k>0 and the product of the roots of equation x to power 2-3kx+2e power 2logk-1=0 is 7 then sum of roots is?

asked by Swathi on May 6, 2018
69. ## algebra

The temperature is dropping 1.5 degrees each hour after 6 hours the temperature is 38 degrees how t write this equation?

asked by Torrie on November 28, 2016
70. ## MATH

Rewrite equation w=exp(2y+8z-3x) as the product of three terms. note that writing exp(a) is the same as writing e^a

asked by DANIELLE on July 11, 2016
71. ## Calculus

Let f(x) = \sqrt[3] x. The equation of the tangent line to f(x) at x = 125 is y = . Using this, we find our approximation for \sqrt[3] {125.4} is

asked by Alessandra Romano on October 31, 2014
72. ## Chemistry

Given the balanced equation : 3 CO + 7 H2 -> C3H8 + 3 H2O How much C3H8 will be produced if 45.8 g CO reacts with 87.3 H2 ? Please all your work (i did it but im not sure if i did all the work right)

asked by Dilcia on July 28, 2015
73. ## Chemistry

If you have constant volume of gas how can you determine the number of moles it has? what equation do you use if your not given the constant volume value?

asked by Sarah on March 29, 2011

The function g(x) is a transformed image of the graph of f(x)=2^x. Write the equation of the transformed function g(x) in the form g(x)= b^x-h+k. f(x) (0,1) (2,4) g(x) (-1,2) (-3,-1)

asked by Anonymous on July 18, 2016
75. ## Chem

How do you write redox reactions. I was given this equation below: 2Mg + O2 --> 2MgO I have to write the redox reaction

asked by Lena on July 29, 2009
76. ## Chemistry

How many grams of zinc must react to give 13.0 grams of ZnO according to the balanced equation. 2 Zn(s) + O2(aq) --> 2 ZnO(s)

asked by Lindt on March 18, 2013
77. ## algebra

given the following quadratic equation, determine if it has a maximum or a minimum value. Then find the maximum or minimum value f(x) - -11x^2 - 2x - 7

asked by anon on December 1, 2011
78. ## Math

Hi, any help with this question would be appreciated . The graph of y = −3x2 +6x + 9 is a parabola. Is the parabola u-shaped or n-shaped? How can I tell this from the equation?

asked by Sam on June 1, 2010
79. ## Math

Hi! Can someone help me with this? Thanks! Directions: Solve this equation by doing it twice; one time using the substitution method and one time using the graphing method. x – 2y = 0 3x – y^2 = 0

asked by Lori on March 2, 2015
80. ## linear algebra

Let S be the plane defined by 2x+4y+2z = 4, and let T be the plane defined by x+3y+3z = 2. Find the vector equation for the line where S and T intersect.

asked by dan on September 29, 2018
81. ## algebra

1.)Find the equation of the circle with center (1, 3) and radius r =2. 2.)Find the area of the circle of the above problem?

asked by Shan on December 5, 2010
82. ## math

find the vertex,focus and equation of the direction of y=-1/16(x-6)^2+3 Y=1/2p(x-h)^2+k p=8 h=6 k=3 (6,3) so vertex is (6,3), focus is (6,-1) and directrix = y=7 Is this correct?

asked by sara on October 21, 2018
83. ## math

I must simplify this equation and am having a hard time (5+2a+3a)-(a2+a-6) I also would like to know if you could help me with this onex(4x2+3x-5)-2(4-x2) this is also simplifing. I have a really hard time with these, thank you

asked by kristina on March 6, 2008
84. ## maths

how do i solve the following equation? 4 - x = 2 - (3 - 2x) remove ( ) by distributing - sign 4-x=2-3+2x then add -4 to both sides to get -x = -4 + 2 -3 + 2x then -x = -5 +2x then add 2x to both sides x=-5

asked by sarah on May 12, 2007
85. ## Math

Hi! Can someone help me with this? Thanks! Directions: Solve this equation by doing it twice; one time using the substitution method and one time using the graphing method. x + 2y = 1 5x – 4y = -23

asked by Lori on March 1, 2015
86. ## trigonometry

solve the equation: 4 tan^2 x + 12 sec x +1 =0, for 0 degrees is less than or equal to x is less than or equal to 360 degrees.

asked by lindsay on May 1, 2012
87. ## Algebra

I have to use this equation to get the answer (t)=time. V=S+a*t I divided t by both sides, but get a little confuse do I divide V by both sides as while is the answer: t = V/s+a/S??

asked by Angie on October 4, 2012
88. ## math

write the equation in slope-intercept form. What are the slope and y-intercept? -12x+13y=-10

asked by kaitlyn on January 8, 2018
89. ## Pre-Cal

Find an equation of the tangent line to the parabola at the given point, and find the x-intercept of the line. 17) x^2=2y , (-3,9/2) 18) y=-2x^2 , (-1,-2)

asked by Mike on April 15, 2009
90. ## Math

Write a percent equation that can be used to solve the following problem: 820 is 20% of what number? A. n = 0.2 x 820 B. 820 = 0.2 × n C. 0.2 = n × 820 D. none of these

asked by PLZ HELP I NEED THE ANSWER ASAP!!! on November 13, 2017
91. ## Math

A function is described by the equation f(x)=x^2-3. The replacement set for the independent variable is (2,4,7,9) What is the corresponding set for the dependent variable

asked by M on April 9, 2015
92. ## math help plz2!!!!

Find an equation of parabola that has the indicated vertex and whose graph passes through the given point. Vertex (-3,5) Point (-6,1)

asked by julissa on June 8, 2014
93. ## Algebra

Write the point-slope form of an equation for a line that passes through each point with the given slope. (2,2),m=-3 This is one example, I'm not sure how to do this.

asked by Brooke on January 14, 2009
94. ## Algebra

Write an equation in point-slope form of the line that has a slope of 1/2 and passes through the point (5,-2)

asked by Sleepy on January 8, 2019
95. ## math

If there are 36 buttons in a jar and there are 3 times as many white buttons than red, how many of each are in the jar? What is the equation and how do I solve?

96. ## Algebra

Write a slope-intercept equation of the line whose graph is described. Perpendicular to the graph of y = x; y-intercept (0,0).

asked by Manuel on May 23, 2012
97. ## Algebra 8th

For each sequence defined recursively, write the first few terms. Then use the terms to write an explicit equation. a(1)=17 a(n+1)=a(n)-3 And a(1) =20. a(n+1)=1/2*a(n)

asked by Summer on January 7, 2017
98. ## Calculus

Find the slope of the tangent line to the curve y = (x^2 -8)^6 at x = 3, and write the equation of the tangent line.

asked by Preston on October 18, 2010
99. ## Precalculus

State whether or not the equation is an identity. Prove your statement. sin(x)/cos(x)+ cos(x)/1+sin(x)

asked by Anonymous on December 5, 2010
100. ## Pre-Calculus

Determine whether the equation represents y as a function of x. |y| = 4 - x If I plug in 5, then I get -1, but it also means 1. Does that mean y has 2 values which means that it is not a function?

asked by Peter on August 9, 2012