Guido

Most popular questions and responses by Guido
  1. Self-Taught Mathematicians

    Those of us who love math certainly know two basic facts about Mr. Gottfried Wilhelm Leibniz: (1) He and Newton (our calculus guy) did not get along AND (2) Mr. Leibniz was a self-taught mathematician My question is for all tutors here who love math. What

    asked on February 22, 2008
  2. Math...For All Math Tutors

    I would like to know how many of the people answering math questions here are current math teachers, were math teachers at one time, are current tutors working for a tutoring company or simply love math. What's your story? I would love to hear from all

    asked on February 15, 2008
  3. What Makes A Good Math Teacher?

    I think a good math teacher is someone who can explain math topics at the level of students. A good math teacher is someone who does not try to impress students with his or her math skills (college math professors are famous for boasting). In your opinion,

    asked on February 22, 2008
  4. Education/Subbing

    How many sub teachers can really say that they are happy working as a sub teacher? Look deep inside and honestly answer the question: Are You Happy Subbing?

    asked on February 22, 2008
  5. Education

    I was wondering how sub teachers survive during the long summer months when there is no pay, especially if you live alone and must pay rent. If you are a sub who lives alone, what plans do you have for YOUR future, financially speaking? Do you save money

    asked on February 22, 2008
  1. math

    Multiply all numerators and all denominators together. Then, reduce the fraction, if needed. Multiplying numerators: 3 x 1 x 2 = 6 Multiplying denominators: 4 x 2 x 3 = 24 We now have this new single fraction: 6/24 Can we reduce this fraction? Yes, we can.

    posted on February 22, 2008
  2. Self-Taught Mathematicians

    Reiny, Isn't it true that both men "invented" calculus independently, though Newton discovered it first? For some reason, they often argued, mathematically speaking.

    posted on February 22, 2008
  3. algebra

    We have a fractional equation: 5/8*t + 2/15*t = 17/20 Our first goal is to find the LCD. What is the LCD of 8, 15 and 20? How about 120? Yes, LCD = 120. We now multiply each term on BOTH sides of the fractional equation by 120 to do away with ALL the

    posted on February 22, 2008
  4. Math

    You were given: Find a number such that 32 is 60% of the number. NOTE: Decimal answer rounded to nearest tenth. Let x = number we want to find The word [of] means to MULTIPLY in math. The word [is] means EQUAL. We now have this equation: 32 = 0.60(x)

    posted on February 22, 2008
  5. Math

    Let x = original budget Formula to use: amount spent = given percent times x $3000 = 1.25(x) Divide both sides by 1.25 to find x. $3000/1.25 = x $2400 = x

    posted on February 22, 2008
  6. Trigonometry

    I want to expand drwls' reply. First, convert 2 miles to feet. If 1 mile = 5280, then 2 miles = 10,560 feet. Secondly, you must re-arrange the given formula because we are looking for an angle NOT height or distance on ground. Let t = theta FOR SHORT.

    posted on February 22, 2008
  7. Math

    Those are the rules for multiplication of signed numbers.

    posted on February 21, 2008
  8. Shapes

    It is a "sector" of a circle with two radii and a small piece of the circle that we call a sector. Damon is right.

    posted on February 21, 2008
  9. Shapes

    A half-moon-shaped.

    posted on February 20, 2008
  10. math

    We have the decimal number: 15.35, which becomes 15(35/100). The fractional part can be reduced. What is the biggest number that can evenly fit into 35 and 100 without a remainder? How about 5? 35/5 = 7 100/5 = 20 Final answer: 5_7/20 =============== The

    posted on February 20, 2008
  11. MATH

    Question 1: 92 - 4 = 88; y = 22 88 - 4 = 84; y = 21 84 - 4 = 80; y = 20 80 - 4 = 76; y = 19 76 - 4 = 72; y = 18 72 - 4 = 68; y = 17 What's the answer? When x = 68, y = 17. ==================== For question 2: IF Y = X-19, WHAT IS THE VALUE OF X WHEN Y= 34.

    posted on February 20, 2008
  12. math

    s = 2 + 4 + 6 + 8 + 10 s = 30 t = 1 + 3 + 5 + 7 + 9 t = 25 Then: s - t = 30 - 25 s - t = 5 Done!

    posted on February 20, 2008
  13. algebra

    If you think about it, 1/5 is really 5^-1, which is read "five raised to the negative one." 125 becomes 5^3. We needed to have the SAME BASE of 5 on BOTH sides of the exponential equation. We now have this: 5^-1(x - 2) = 5^3 NEXT: Remove the parentheses

    posted on February 20, 2008
  14. trig

    We have trig identities. cscx - sinx to cotx(cos x). cscx is the reciprocal of the sine function. So, then: cscx = 1/sinx We now have: 1/sinx - sinx...Treat this like a fraction case. 1/sinx - sinx becomes (1 - sin^2x)/sinx Of course, (1 - sin^2x) is one

    posted on February 20, 2008
  15. Calculus?

    What is ã mean????

    posted on February 20, 2008
  16. math

    Retype your question.

    posted on February 20, 2008
  17. inequality

    This has nothing to do with inequalities. You are simply looking asymptotes. First of all, what is an asymptote? You need to know the definition of math terms. An asymptote is a boundary line that a graph gets very, very, very close to but NEVER (say

    posted on February 20, 2008
  18. inequalities

    bobpursley, How can you factor x^2 + 9 into (x - 3) (x + 3) when there is a PLUS sign between x^2 and the constant 9? Get my point?

    posted on February 20, 2008
  19. algebra

    Kay, I think Mel is looking for an answer in a different base system. Mel, what base are you talking about? If you are takling about base 10? If so, then the answer is 2. OR... Are you talking about base 3, base 4, base 5, which one?

    posted on February 20, 2008
  20. algerbra

    We have this: 10^7 * 10^3 ------------- = 10^4 * 10^-9 We can multiply the numerators and denominators as step one, if you'd like. 10^7 * 10^3 = 10^10 = our numerator. 10^4 * 10^-9 = 10^-5 = our denominator. We now have this fraction: 10^10/10^-5 Since we

    posted on February 20, 2008
  21. Algebra

    I want to say what Damon said in a different way. In the y-intercept equation y = mx + b (an equation that represents linear functions), the domain is ALL REAL NUMBERS going from negative infinity to positive infinity; the range is also ALL REAL NUMBERS y.

    posted on February 20, 2008
  22. Math

    We have composite functions here. You are given: If g(x)= 3x-8, find g[g(-4)]. By the way, g[g(-4)] can also be written g(g(-4)) and it's read: "g of g of negative four." We are looking for g of g of x first. To do so, replace x in (3x - 8) with the value

    posted on February 20, 2008
  23. Math

    3b. Pick any two points on the line and find the slope of the line. The slope is a numerical value that describes just how slanted a given line is. Here is is an example of finding the slope of a line. SAMPLE: Given the points (3, 4) and (8, 9), find the

    posted on February 20, 2008
  24. Pre-Algebra

    3a. The y-intercept is found when you set x to = 0. The y-intercept is the point where the graph of the line crosses the y-axis. SAMPLE: In the equation y = 3x + 5, what is the y-intercept? It is the point (0,5). Do you see number 5? That number represents

    posted on February 20, 2008
  25. Math

    Do what I said. Use the quadratic formula or completing the square. You can search the net for many math sites that easily teach you about the quadratic formula and/or completing the square.

    posted on February 19, 2008
  26. nystce exam

    Go to your local public library. They have the guides plus plenty of material that will help you prepare for the exams. I took the LAST in April 2001 and scored very high on it. You can also go to the UFT. They offer training courses for a reasonable fee

    posted on February 19, 2008
  27. math

    Multiply: 248 times 63 = 15,624

    posted on February 19, 2008
  28. Math

    Okay, you want to factor this equation, right? We have this: y^2 - 4y - 2 = 0 You can use the quadratic formula or completing the square to solve this question.

    posted on February 19, 2008
  29. algebra 1

    We have: sqrt{60} = We have to break the radicand down (our 60). What two numbers (one of them must be a perfect square) multiplied together will produce 60? How about sqrt{4} times sqrt{15}? Yes, sqrt{4} times sqrt{15} = sqrt{60} and the sqrt{4} is a

    posted on February 19, 2008
  30. Math

    I answered this question. You need to be more specific, please.

    posted on February 19, 2008
  31. Math

    We have a quadratic equation here. Do you want to factor this equation? What exactly do you want to do with this equation?

    posted on February 19, 2008
  32. math

    If that is the case, then this should be a new question and thus a new topic.

    posted on February 19, 2008
  33. Pre Cal

    We use sine = opp/hyp Let x be the height of the slope that we are seeking. sin(25.2 degrees) = 1808 feet/x Multiply both sides by x and we get: sin(25.2 degrees)(x) = 1808 feet Next: Divide both sides by sin(25.2 degrees) to find x. x = 1808 feet/sin(25.2

    posted on February 19, 2008
  34. 7th grade math

    x + 4 (x + 3) This is not a FOIL situation. You must first clear the parentheses. 4 times x = 4x 4 times 3 = 12 We now have: x + 4x + 12 Combine like terms is our next step. x + 4x = 5x Final answer: 5x + 12 Done!

    posted on February 19, 2008
  35. math

    You have to tell us what 31.4cm represents. Does it represent the radiu or diameter? Which one? 78.5 squared means to multiply 78.5 by itself. 78.5 x 78.5 = 6162.25 What does 6162.25 have to do with 31.4cm? Please, clarify your question.

    posted on February 19, 2008
  36. MATH

    Do you have a sample question?

    posted on February 19, 2008
  37. Math

    Use the factor tree method to solve both questions.

    posted on February 19, 2008
  38. math

    Do you have sample questions?

    posted on February 19, 2008
  39. basic math

    Do you have a question for me?

    posted on February 19, 2008
  40. Math

    87 x 86 x 85 x 84 x 83 = ???

    posted on February 19, 2008
  41. math

    This is not a math question.

    posted on February 19, 2008
  42. math

    What is spens? This is not a math question.

    posted on February 19, 2008
  43. Geometry

    Graph all the points given on the xy-plane. If you get a picture of a KITE, then the answer is yes. Of course, I graphed all the points for you and determined that the given 4 points form a picture of a kite. Done!

    posted on February 18, 2008
  44. Algebra

    Can I break what down step by step?

    posted on February 18, 2008
  45. pre-algebra

    Damon, I got the same answers except I replied using fractions.

    posted on February 18, 2008
  46. pre-algebra

    Here is some information for you: There are 86,400 seconds in one day. There are 3 feet in one yard = 36 inches in one yard. 3/86,400 = 1/28,800 days. 2/36 = 1/18 inches. Is this what you wanted?

    posted on February 18, 2008
  47. Math

    Mike, After doing the question again, I realize that 4x - x^2 is not one-to-one. Hence, it has no inverse function. Sorry....The answer is: NO INVERSE FUNCTION HERE.

    posted on February 18, 2008
  48. math :]

    I already answered this question. All fractions are rational numbers.

    posted on February 18, 2008
  49. Math

    A rational number is a number that can be written as a fraction. 14/3 is an improper fraction and thus rational.

    posted on February 18, 2008
  50. Algebra

    Yes, you can. Here is a sample literal equation. Solve for h. h + rt = j Subtract rt from both sides to find h. h = j - rt Done! I just solved for h, which is a variable. Solving for variables is very common in the world of algebra.

    posted on February 18, 2008
  51. Algebra

    An equation has an EQUAL ( = ) sign; an expression does not. Sample Equation: 3x + 5 = 10 Sample Expression: 30x + 40y See the difference?

    posted on February 18, 2008
  52. math

    First, find the circumference of the circle with diameter 5 feet. We use this formula: C = pi x d, where pi = 3.14 and d = 5 feet C = 3.14 x 5 feet C = 15.7 feet Now multiply 15.7 feet by $3 and you will find how much it will cost to have the top

    posted on February 18, 2008
  53. pre-algebra

    Is there a typo here? You meant 3 seconds? There are 24 hours in one day. 60 minutes = 1 hour. 60 seconds = 1 minute. How many minutes in one day? 60 x 24 = 1440 minutes in one day. How many seconds in one day? 1440 x 60 = 86,400 seconds in one day. How

    posted on February 18, 2008
  54. math

    Find the area of the given triangle as step 1. A = 1/2(base)(height)....This is the general formula used to find the area of a triangle when base and height are given. A = 1/2(30)(20) A = 1/2(600) A = 300 square feet The front will cost $3 per square feet

    posted on February 18, 2008
  55. Math

    You were given: y = 4x - x^2 We switch x and y. x = 4y - y^2 Factor the right side of the equation. x = y(4 - y) Next: xy = 4 - y Add y on both sides of the equation. xy + y = 4 Factor on the left side. y(x + 1) = 4 Isolate y on the left side. y = 4/(x +

    posted on February 18, 2008
  56. pre- algebra

    new price = $30 The new price (or $30) = 3x - 6 old price = x We now equate: 30 = 3x - 6 30 + 6 = 3x 36 = 3x 36/3 = x 12 = x Old Price = $12. Done!

    posted on February 17, 2008
  57. math

    Yes, you are right.

    posted on February 17, 2008
  58. pre- algebra

    Joshua did a great job! I just want to say that to solve for a variable (any variable) means to isolate the variable on one side of the equation. Do you see, as Joshua said, that t = 13? Do you see that the letter or variable t has been isolated on one

    posted on February 17, 2008
  59. math

    48/60 = x/300 We now cross-multiply. 60(x) = 48(300) 60x = 14,400 x = 14,400/60 x = 240 So, what is the fraction? 240/300 What does 240/300 really mean? It means that if we were to reduce it to the lowest term, we would end up with 48/60. Why? Because they

    posted on February 17, 2008
  60. Algebra

    We have this: (y -< x + 2) = point 1. (x + 2 -< 6) = point 2. (y >- -2) = point 3. Replace all inequality symbols with an equal sign for easy simplification. Point 3: y >- -2 becomes y = -2 We just found y. We plug y = -2 in point 1 to find x. -2 = x + 2

    posted on February 17, 2008
  61. Algebra

    The way you typed your questions is not clear. Please use proper keyboard symbols.

    posted on February 17, 2008
  62. Algebra II

    Well-done!

    posted on February 17, 2008
  63. Math

    Well, 16 feet = 192 inches. 13_3/8 x 12 = 160_1/2 inches. 192 inches - 160_1/2 inches = 31_1/2 inches. You can also write it as 31.5 inches. You forgot the 1/2. Other than that, good job!

    posted on February 17, 2008
  64. algbra

    I guess you meant to type: y^-5 times y^-10. Well, y^-5 becomes 1/y^5. Also, y^-10 becomes 1/y^10. We now have this: (1/y^5) times (1/y^10) = 1/y^15

    posted on February 17, 2008
  65. math

    Sue = 1/45 Bill = 1/65 Together = 1/x 1/45 + 1/65 = 1/x We have a fractional equation. Solve for x. What is the LCD of 45, 65 and x? It 585x. We now multiply every term on BOTH sides of the fractional equation by the LCD. (1/45)(585x) + (1/65)(585x) =

    posted on February 17, 2008
  66. algebra

    You can only add or subtract two polynomial terms together if they have the same variables; terms with matching variables are called "like terms." Radicals work in a very similar way. Sample radical expression: 3(sqrt{2xy}) - 2(sqrt{50xy})

    posted on February 17, 2008
  67. calculace

    First of all, it is spelled calculus. Next, show your work so that we know where you need help. Okay?

    posted on February 17, 2008
  68. algebra

    In order to to add or subtract radicals together, they must be like radicals; in other words, they must have the EXACT same radicand and index. This is the main reason why we must simplify them. If you are asked to add or subtract radicals that have

    posted on February 17, 2008
  69. math

    We have a fractional equation. Your first goal should be to do away with the fractions. It is easier to work with equations that have no fractions. What is the LCD of 21 and 49? Reiny said 147. 147/21 = 7 147/49 = 3 Yes, 147 = LCD. We multiply each term on

    posted on February 17, 2008
  70. math

    Formula needed is: A = 1/2(base)(height) 44 = 1/2(x + 3)(x) One leg is 3m longer than the other can be expressed as (x + 3). The other leg is simply the letter (x). In other words, (x + 3) is one of the legs and the letter (x) is the other leg. This is

    posted on February 17, 2008
  71. maths

    Good point and you are right. I did not capture that part of the question. Good looking out, Reiny. Thanks for the correction.

    posted on February 17, 2008
  72. calculace

    First of all, it is spelled calculus. Next, show your work so that we know where you need help. Okay?

    posted on February 17, 2008
  73. maths

    The word half = 1/2. Four fifths = 4/5. To find the answer, we subtract 1/2 from 4/5. Now: 1/2 = 50 4/5 = 80 80 - 50 = 30 30 = 3/10 Done!

    posted on February 17, 2008
  74. Algebra

    I will do number one only. We have this: (1)Find x in the solution of the system 3x + y = 2 and 2x -3y = 16. (A)2 (B)-4 (C)18/11 (D)10/11 Your choice = (A) We have a system of linear equations in two variables. Here are the two equations: 3x + y =

    posted on February 17, 2008
  75. math probabilty

    This question is incomplete.

    posted on February 17, 2008
  76. maths

    We have: I am a three digit number. My tens digit is twice my ones digit, my hundreds digit is twice my tens digit. I am greater than 500. Who am I? How about 631? 631 is > 500. This is a math riddle not a math question. There are several answers.

    posted on February 17, 2008
  77. geometry

    What is your geometry question? What exactly do you need help with in terms of geometry? Write back....

    posted on February 16, 2008
  78. Quadratic equations still

    The solutions are found at the location (x ,0), where x represents any value and 0 represents the y coordinate. Three samples: (4, 0), (-6, 0) and (-1/2, 0)

    posted on February 16, 2008
  79. math

    To pick up on what drwls said, in terms of prime factorization, we can also write the example given using exponents. The prime factorization of 120 = 5 x 3 x 2^3, where 2 is raised to the third power.

    posted on February 16, 2008
  80. Math

    This question does not make sense. What are the instructions? What do you want to do with your fraction?

    posted on February 16, 2008
  81. algebra

    What is the slope of the line? The slope of a line is equal to the following fraction: (number of vertical units it takes to travel from one point to another)/(number of horizontal units it takes to travel from one point to another. The letter m has been

    posted on February 16, 2008
  82. Math

    Babygirl, You have the same question as babygirl. Does Bybygirl = Tim and vice-versa? To find the final exam score, add all the scores and then divide by the number of scores listed, which is 15. ============================== Median is the middle value of

    posted on February 15, 2008
  83. Math

    Ms. Sue knows that Tim = babygirl, right?

    posted on February 15, 2008
  84. Math

    Tim, You have the same question as babygirl. Does Tim = babygirl and vice-versa? To find the final exam score, add all the scores and then divide by the number of scores listed, which is 15. ============================== Median is the middle value of a

    posted on February 15, 2008
  85. Math...For All Math Tutors

    Very interesting reply. I wish your son the best in the world. He is a very smart and will always be successful. Math can either break you and make you. It depends on the person and the choices we make. It's sad to know that colleges don't tell the truth

    posted on February 15, 2008
  86. Trig

    Good job Reiny. Guido

    posted on February 15, 2008
  87. Right triangle

    The easiest way is to use the distance formula for points in the (x,y) form. Use the formula 3 times. You have triangle GHJ. Use the formula from point: G to H H to J G to J Only then will you be able to tell if triangle GHJ is a right triangle or not.

    posted on February 15, 2008
  88. Mth finding modes

    Again, the mode is a number that appears more than the rest on a given list. There is no mode in your list because each number appears JUST ONE time. Get it?

    posted on February 15, 2008
  89. math

    The Mean is the average. 1-We add the number of miles driven. 238 + 159 + 87 + 163 + 198 = 845 2-We now divide 845 by 5. 845/5 = Mean 169 miles = Mean Done!

    posted on February 15, 2008
  90. Math find the mode

    The mode is the number that is listed the most. You can see that 9 appears more than the rest of the numbers. Then, 9 is the mode.

    posted on February 15, 2008
  91. Algebra

    This question is incomplete.

    posted on February 15, 2008
  92. algebra

    What equation? Where is the equation?

    posted on February 15, 2008
  93. trigonomitry

    Use a trig function that states opposite/hypotenuse. Of course, this would be the sine function. sin(45degrees) = h/7meters Let h = height of building sin45 = h/7 sin45 times 7 = h 4.949747468 = h Round 4.949747468 to the nearest tenths becomes 4.95

    posted on February 15, 2008
  94. Algebra

    Here it is: First multiply 7 x 1/2 = 7/2. We now have this equation: 42 = 7/2(b1) + 9) Simplify the right side of the equation and the whole thing becomes 42 = 7/2(b1) + 63/2 Subtract 63/2 from 42. 42 - 63/2 = 10_1/2 We now have: 10_1/2 = 7/2(b1) 10_1/2

    posted on February 15, 2008
  95. Algebra

    I will set it up for you and you can simplify. A = 42 h = 7 b2 = 9 I will plug and you can chug. 42 = 1/2(b1 + 9)(7) Solve for b1, which is read "b sub one." Can you take it from here?

    posted on February 15, 2008