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Proving a quadrilateral is a rectangle |
2007-07-14 |
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From Sonja:
I was having this discussion with another teacher and we need a third opinion. When you are trying to prove a quadrilateral is a rectangle which method should you use:
- Prove the shape is a parallelogram by doing slope 4 times by stating that parallel lines have equal slopes. Then proving a right angle by stating that perpendicular lines have negative reciprocal slopes.
- Doing the slope 4 times and stating that the shape is a rectangle because opposite sides are parallel because of equal slopes and it contains a right angle because of negative reciprocal slopes.
I guess the real question is do you have to first state that the shape is a parallelogram?
Answered by Stephen La Rocque. |
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Comparing flow rates of two pipes |
2007-07-14 |
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From Kenneth:
If two water pipes are 3 feet long, but one of them has a 1 foot diameter and the second has a 1 1/2 foot diameter, what simple mathematical method can be used to determine how much faster one pipe can drain water than the other pipe?
Answered by Stephen La Rocque. |
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Implicit Derivatives |
2007-07-13 |
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From Charles:
I need help computing y' by implicit differentiation the question is:
y^2 + x/y + 4x^2 - 3
Answered by Stephen La Rocque. |
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Any regular polygon inscribed in a circle |
2007-07-12 |
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From DJ:
Circle with r=12" is inscribed in a regular octagon. What is the length of each octagon segment?
Note: Our answer works for any regular polygon inscribed in any circle.
Answered by Stephen La Rocque. |
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Length of a circle |
2007-07-11 |
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From Debra:
i have a radius of 73 inches, i need to know the length of the circle please.
Answered by Stephen La Rocque. |
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Discount percentage |
2007-07-11 |
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From Greg:
List Price: $50.00
Discount: 33 1/3%
What would the net price be?
Answered by Stephen La Rocque. |
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Compound interest |
2007-07-11 |
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From Michelle:
Present Value of $1500 to be paid in Year 7, with an interest rate of 12%
Answered by Stephen La Rocque. |
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Converting measurements |
2007-07-11 |
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From Nicole:
if you have 8 oz of water how many cc: will there be.
Answered by Stephen La Rocque. |
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Calculating sales taxes |
2007-07-11 |
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From Tonya:
Hi, Im having trouble calculating GST and PST
I know that in this province, GST is 6% and PST is 7%, I have a total of $275, and GST is 0.06, and PST is 0.07, so do I add those two and multiply them by the total, $275?
Answered by Stephen La Rocque. |
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The probability of rolling double sixes twice in a row |
2007-07-10 |
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From Matt:
what is the probability of rolling double sixes twice in a row?
Answered by Stephen La Rocque. |
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Grams of vodka |
2007-07-10 |
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From Andrew:
milliliters to grams..vodka 80 proof?
Answered by Stephen La Rocque. |
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How many women and men math students are there? |
2007-07-09 |
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From Bing:
there are 38 math students. How many men and women strudents are there if the women exceeded one half of the men by 17?
Answered by Stephen La Rocque. |
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Derivative of a Function |
2007-07-09 |
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From Bob:
What is the derivative of the function a sub n = [n/(n+1)]^n ?
Answered by Stephen La Rocque. |
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Dried grapes and percentage of water content |
2007-07-09 |
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From Jyoti:
Fresh grapes contain 90% water by weight while dried grapes contain 20 % water by weight. what will be the weight of dry graprs available from 20kg of fresh grapes?
Answered by Stephen La Rocque. |
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loga b + logb a < 0 |
2007-07-08 |
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From Claire:
Suppose a, b are real numbers taking all positive values except 1, determine (without the use of calculators) whether there exists values of a and b such that loga b + logb a < 0
Answered by Penny Nom. |
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