# Posts by Alexa

Total # Posts: 396

**math**

If sina+7sinb=4 (sinc+2sind) and cosa+7cosb=4 (cosc+2cosd), how do I prove that 2cos(a-d) =7cos(b-c)?

**Math**

Hello, What are the different formulas for circles (radius, circumfrence, diameter, area)? Thank you

**Physics 2**

The temperature of a tungsten sample is raised while a copper zample is maintained at 20?. At what temperature will the resistivity of the tungsten sample be four times that of the copper sample?

**accounting**

A credit customer paid $850 toward his accounts receivable. The accountant recorded a credit to the revenue account. This error would cause __________. A. revenue to be understated B. cash to be overstated C. accounts receivable to be overstated D. liabilities to be ...

**Math**

Miss Lee spent $840 on a vacation. She spent two thirds of the amount on a train ticket and half of the remaining amount on food. How much did she spend on the ticket and food all together?

**Physics 2**

? of gold is 14.3x10^-6/C°. The density of gold is 19.3 g/cm^3 at 20?. Determine its density at 140?.

**math**

Given: ?KLM, KL = LM = 13in, KM = 10in. Find: The area of ?KLM

**Geometry**

Given: ????, m?ACB = 90° m?ACD = 30° AD = 8 cm. Find: CD, Perimeter of ?ABC plz add answer

**High School Geometry**

Given: ?AKL, AK = 9 m?K = 90o m?A = 60 ° Find: The perimeter of ?AKL The area of ?AKL 1/ AK perpendicular to LK 2/AL is the third side plz add answer and solution

**High School Geometry**

Given: ?TSP, TS = SP = 10cm, TP = 12cm. Find: Three altitudes of ?TSP. for this one I only got one of the altitudes 2 ?61 can you give me the other two and tell me if this one is right, sorry I am in a rush

**High School Geometry**

In isosceles ?ABC, AC = BC, AB = 6 in, CD ? AB , and CD =? 3 in. Find the perimeter of the isosceles triangle. Can u plz put answer and equation thanks, :)

**High School Geometry**

what should I do with the area of the triangle? should I subtract it from the area of the quarter of the whole circle? and to find the perimeter should I find the perimeter of the whole circle then divide it by 4? thanks for your help Reiny! :)

**High School Geometry**

The figures in (a) and (b) below are made up of semicircles and quarter circles; the figure in (c) shows a quarter of a circle in a square. Find the area and the perimeter of each figure in terms of Ï€. since I can't put a URL to the pic I will try to describe it...

**chemistry**

how can i determine via infrared spectrum whether the alcohol that was oxidized was primary or secondary? i did a lab experiment in which we oxidized a diol with bleach and i need to figure out which -OH group was oxidized into a C=O. What are the signs of whether the -OH is ...

**chemistry**

Hi, I'm doing a post-lab report and I have no idea how to solve this question. It asks which of the following molecules would be useful in quenching benzophenone photoreduction. it then lists oxygen (s1 = 22kcal/mol), 9,10-diphenylanthracene (t1=42 kcal/mol), trans-1,3-...

**Math**

In rod's family 3/4 of members wear glases. Of those who do not wear glasses, 1/3are male. What fraction of the family are males who do not wear glasses?

**Math**

Chris had a tin of 24 cookies. He has eaten 1/4 of the cookies. How many cookies has he eaten?

**Integral Calculus**

Volume of the area bounded by y=sin(x), x-axis, x is greater than or equal to 0 but less than or equal to pi, revolved about x=3pi/2.

**Math**

larry places $ 520 in saving account that earns 3.2 simple interest. find the total amount in the a count after 2 years

**English**

Which statement is false? A. Parentheticals aren’t crucial to the meaning of a sentence. B. Parentheticals are like asides. C. Parentheticals are crucial to the meaning of a sentence. D. Parentheticals are like comments. Is it C.?

**Math**

How can i know where to place the Ford y digit of a quotient

**math**

Tonya's mother is 1.5 times as tall as Tonya was when she was 6. How tall is Tonya's mother? Use the correct number of significant digits.

**Calculus**

Integral of (3^x)(e^x)dx

**English**

Was the Victorian Era big on classism?

**Maths**

T=25+R R=25-5=20 20+25=45 T=45 R=20

**Pre-Calculus**

Your computer supply store sells two types of laser printers. The first type, A, has a cost of $86 and you make a $45 profit on each one. The second type, B, has a cost of $130 and you make a $35 profit on each one. You expect to sell at least 100 laser printers this month and...

**Pre-Calculus Matrix**

Use Gaussian elimination to find the complete solution to the system of equations, or state that none exists. Show your work. 4x - y + 3z = 12 x + 4y + 6z = -32 5x + 3y + 9z = 20 4 -1 3 12 1 4 6 -32 5 3 9 20 I believe that the solution does not exist and how can I prove that?

**Pre-Calculus**

thank you!

**Pre-Calculus**

Solve the system of equations using matrices. Use Gaussian elimination with back-substitution. x + y + z = -5 x - y + 3z = -1 4x + y + z = -2 I really need help.. 1 1 1 -5 1 -1 3 -1 4 1 1 1 -2 I've done so many different methods to solve this and I get stuck..

**Pre-Calculus**

The Fiedler family has up to $130,000 to invest. They decide that they want to have at least $40,000 invested in stable bonds yielding 5.5% and that no more than $60,000 should be invested in more volatile bonds yielding 11%. How much should they invest in each type of bond to...

**Math**

The answer is -3m - 7

**Calculus**

A particle moves along the curve y=lnx so that its abscissa is increasing at a rate of 2 units per second. At what rate is the particle moving away from the origin as it passes through the point (1,e)?

**Differential Calculus**

Thank you Sir ☺

**Calculus**

Thank you so much

**Calculus**

Sorry for asking, but why did tan(a) become 8/x and tan(b) 18/x?

**Calculus**

A statue 10 feet high is standing on a base 13 feet high. If an observer's eye is 5 feet above the ground, how far should he stand from the base in order that the angle between his lines of sight to the top and bottom of the statue be a maximum?

**Calculus**

A particle travels along the parabola y=ax^2+x+b. At what point do its abscissa and ordinate change at the same rate?

**Calculus**

Air expands adiabatically in accordance with the law PV^1.4=Const. If at a given time the volume is 14 cubic feet and the pressure is 40 pounds per square inch, at what rate is the pressure changing when the volume is decreasing 1 cubic foot per second?

**Calculus**

thank you so much!

**Calculus**

Find the area of the largest rectangle with sides parallel to the coordinate axes which can be inscribed in the area bounded by the two parabolas y=26-x^2 and y=x^2+2

**Calculus**

Thank you sir.

**Calculus**

An open box is formed from a piece of cardboard 12 inches square by cutting equal squares out of the corners and turning up the sides, find the dimensions of the largest box that can be made in this way.

**Math**

Assuming that the question is how many buses do you need to transport those 450 students if 50 students can fit on a bus, you would just divide 450 by 50. For the second part of the question, add 10 to the 450 and divide by 50 again rounding up to the next whole number since ...

**Chemistry**

how would you prepare pure dry crystals of potassium trioxonitrate?

**Chemistry**

Question: write the balanced equations for the titration of oxalic acid (C2H2O4) with KOH. Work so far: I know that the overall equation is COOH)2 + 2KOH ------.> (COOK)2 + 2H2O but I am unsure how to proceed to the two step-wise equations

**Math**

Oh okay!! Thank you!!!

**Math**

Okay, so then, 348 x .0809 x 2 will equal P?

**Math**

marisol owed $384 in interest after a 24 month loan with a simple interest rate of 8.09%. What was the initial amount of the loan?

**Algebra**

Consider the leading term of the polynomial function. What is the end behavior of the graph? Describe the end behavior and provide the leading term. -3x5 + 9x4 + 5x3 + 3 how would I solve this?

**Algebra**

Consider the leading term of the polynomial function. What is the end behavior of the graph? Describe the end behavior and provide the leading term. -3x5 + 9x4 + 5x3 + 3 how would I solve this?

**Algebra**

Evaluate sqrt7x (sqrt x-7 sqrt7) Show your work. sqrt(7)*sqrt(x)-sqrt(7)*7*sqrt(7) sqrt(7*x)-7*sqrt(7*7) sqrt(7x)-7*sqrt(7^2) x*sqrt 7x-49*x ^^^ would this be my final answer?

**Algebra**

okay..But why does it say show your work? how would I show it?

**Algebra**

A manufacturer of shipping boxes has a box shaped like a cube. The side length is (5a + 4b). What is the volume of the box in terms of a and b? Show your work. (5a+4b)^3 =(5a+4b)(5a+4b)(5a+4b) =(25a2+40ab+16b2)(5a+4b) = 125a^3 + 100a^2b + 200a^2b + 160ab^2 + 80ab^2 + 64b^3 = ...

**algebra**

(5a+4b)^3 =(5a+4b)(5a+4b)(5a+4b) =(25a2+40ab+16b2)(5a+4b) = 125a^3 + 100a^2b + 200a^2b + 160ab^2 + 80ab^2 + 64b^3 = 125a^3 + 300a^2b + 240ab^2+ 64b^3 would this be correct now?:)

**algebra**

A manufacturer of shipping boxes has a box shaped like a cube. The side length is (5a + 4b). What is the volume of the box in terms of a and b? Show your work. (5a+4b)3 =(5a+4b)(5a+4b)(5a+4b) =(25a2+40ab+16b2)(5a+4b) = 125a3 + 100a2b + 200a2b + 160ab2 + 80ab2 + 64b3 = 125a3 + ...

**Algebra**

thank you!

**Algebra**

For the given quadratic equation convert into vertex form, find the vertex, and find the value for x = 6. Show your work. y = -2x2 + 2x +2 -(1/2)y = x^2 - x - 1 (-1/2)y + 1 = x^2 - x (-1/2)y + 1 = (x - 1/2)^2 - 1/4 (-1/2)y = (x-1/2)^2 - 5/4 y = -2(x-1/2)^2 + 5/2 would this be ...

**algebra**

Let f(x) = -2x - 7 and g(x) = -4x + 3. Find (f o g)(-5) A. -9 B. 3 C. 23 D. -53 could you help me with this one? Would it be c?

**algebra**

Let f(x) = -3x - 4 and g(x) = 2x - 6. Find (f o g) (-7) A. 28 B. -20 C. 17 D. 56 I think it'll be A?

**algebra**

What are the vertex, axis of symmetry, maximum or minimum value, and range of y=-5(x+2)^2-8? please explain to me how you would solve this..I don't really understand. The answer is given.. The vertex is (-2, -8); the axis of symmetry is x= -2; k= -8 is the maximum value; ...

**algebra**

its b

**algebra**

What is the equation of the given line in standard form? Use integer coefficients. y = -6.9x + 5.1 A. -69x + 10y = -51 B. 69x + 10y = 51 C. 69x + 10y = -51 D. -69x + 10y = 51 how would I solve it steph by step? I think the answer is C.

**Physics**

An object of mass m = 2.9 g and charge Q = +42 µC is attached to a string and placed in a uniform electric field that is inclined at an angle of 30.0° with the horizontal. The object is in static equilibrium when the string is horizontal. a) Find the magnitude of the...

**Math**

Oh okay! Thank you for the help! I think I understand now. Thank you!

**Math**

Thank you for the help, but I am confused on as to why you used 8 instead of 1/8? Is it because the whole pool is being filled or.. ?

**Math**

4/15 of a pool is filled every 1/8 of an hour. How much of the pool will be filled in one hour?

**Geometry**

What you want to do is find the slope of all 4 sides and you should get to slopes the same...and follow a regular proof till you say its a trap.then to prove its not isosceles you use the for sides again but this time with the distance formula...and then you go along answering...

**American History**

yes please do give me your interpretation..

**American History**

“There cannot be a great vice president. A great man may occupy the office, but there is no way for him to become a great vice president because the office in itself is almost wholly unimportant.” —former Vice President John Nance Garner, Collier’s ...

**American History**

thank you

**American History**

The Department of Homeland Security protects the United States against terrorism. (a) List three of the five main services that it provides. (b) Why do you think the work of this department is so complex?

**Math**

A person who is 60in. tall casts a shadow that is 15in. long. How tall is a nearby tree that casts a shadow that is 40 in. long?

**Math**

The answer for part a. is $4.67 less per pound. You have to convert $9.70 to per pound. First you divide it by 2.5 pounds to get $3.88 per pound. Then you subtract that from $8.55 and you get the answer $4.67. The answer for part b. is $2.27. First you have to multiply $8.55 ...

**Math**

Johnny spent 4 2/3 for his exams studying for his math exams. He spent 3/4 of the time studying for math. How many hours did Johnny spend stydying for his exam? How do I show the number sentence?

**AP chem**

The experiment can be extended to determine the order of reaction m with respect to [OH-] by varying the concentration of hydroxide ions [OH-] Assume that the value of the pseudo-rate constant k’ was measured for two different concentrations of [OH-]. The value of k’...

**Geometry**

Jason designed an arch made of wrought iron for the top of a mall entrance. The 11 segments between the two concentric circles are each 1.25 m long. Find the total length of wrought iron used to make the structure. Round the answer to the nearest meter. Show your work. The ...

**Geometry**

75.40 cm^3 would that be the final answer?

**Geometry**

1/3 (pi *r^2)(h) ?

**Geometry**

An hourglass, composed of two identical cones, is 12 cm tall. The radius of each cone is 3 cm. If you want to fill the bottom half of the hourglass 2/3 full of salt, how much salt will you need? Explain the method you would use to find the amount of salt. How would I solve this?

**Geometry**

The equation (x + 5) + (y + 3) = 169 models the position and range of the source of a radio signal. Describe the position of the source and the range of the signals. ???? Would the answer be (5,3) is the center and 13 is the range of signals..??

**Geometry**

2π * 7 * 45 = 630π = 1978.2cm^2 then would that be my final answer?

**Geometry**

Janine wants to paint just the sides of a cylindrical pottery vase that has a height of 45 cm and a diameter of16. Janine wants to paint just the sides of a cylindrical pottery vase that has a height of 45 cm and a diameter of 14 cm. To the nearest whole number, find the ...

**Help me! Geometry**

A design on the surface of a balloon is 5 cm wide when the balloon holds 71 cm^3 of air. How much air does the balloon hold when the design is 10 cm wide? Explain the method you use to find the amount of air. How would I solve this step by step?

**Calculus**

Thank you so much!

**Calculus**

Consider the line through the points (3,2,5) and (1,1,1). Consider the plane A that is perpendicular to this line, and passing through the point (-1,0,2). Consider the plane B that passes through the points (1,-1,0), (0,2,0), and (0,5,2). Consider the intersection of plane A ...

**Calculus**

Consider the line through the points (3,2,5) and (1,1,1). Consider the plane A that is perpendicular to this line, and passing through the point (-1,0,2). Consider the plane B that passes through the points (1,-1,0), (0,2,0), and (0,5,2). Consider the intersection of plane A ...

**Geometry**

Jason designed an arch made of wrought iron for the top of a mall entrance. The 11 segments between the two concentric circles are each 1.25 m long. Find the total length of wrought iron used to make the structure. Round the answer to the nearest meter. Show your work. How ...

**English**

Thank you darling!

**English**

Which sentence has no direct object? A. Read me those directions again, please. B. Can you return this book by tomorrow? C. I just told Janice to call me tonight. D. Hank spoke to the audience for an hour. I think D..

**English**

What is the prepositional phrase in this sentence, and what does it modify? The purpose of the last song was to show off all the musicians’ talents. A. of the last song; an adjective phrase that modifies the noun purpose B. to show off all the musicians’ talents; an ...

**English**

Coyote hid himself and watched the Beings from a distance. He noticed that for a short time when they changed guardians of the fire, it remained unguarded. When the moment was right, Coyote snatched up a flaming piece of fire and raced away, the furious Beings just behind him...

**English**

So it would be D?

**English**

What is the infinitive phrase in this sentence? In August, we went to Ontario and to upstate New York to see Niagara Falls. A. to Ontario B. to upstate New York C. to see D. to see Niagara Falls I think its C

**English**

I was thinking that too.Thank you

**English**

What is the most likely reason that Shakespeare would include a scene in a tragedy that focuses on a minor character who uses a commoner’s dialect and falls over everything? A. to show that he is democratic B. to promote a social cause C. to poke fun at an unpopular ...

**English**

Thank you

**English**

Which of the following sentences contains an infinitive phrase? A. Racing through the park, she paused only to drink. B. Reading by flashlight does not cause bad vision. C. Mom’s idea was to pack the night before our early flight. D. Remembering every opinion in the text ...

**Math**

If I post is put every 6 feet along the fence that is rectangular and nuts 42 feet long and 36 foot wide how many posts do I need

**math**

a chemist wants to create a solution that is 36% acid. How many liters of a 60% acid solution must be added to 30 liters of a 15% acid solution to obtain this 36% acid mixture?

**Math**

Suppose x is an angle in the second quadrant such that cosx=-8/17, what is the value of tan(3x/2)?