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Divisibility by 9 and 11 |
2006-10-04 |
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From Prakai:
can 818991 divisible by 9, or 11?
Answered by Penny Nom. |
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Inequalities |
2006-10-03 |
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From Maleeha:
a)Use algebra to find the set of values of 'x' for which x(x-5)>36.
b)Using your answer to part a, find the set of values 'y' for which y2(y2-5)>36
Answered by Penny Nom. |
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A 5x2 rectangle |
2006-10-03 |
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From Stanley:
Cut a 5x2 rectangle into 4 pieces, and then put them back into as a square.
Answered by Claude Tardif and Penny Nom. |
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1_._ x _._ = _ _.5 _ |
2006-10-03 |
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From Harold:
1_._ x _._ = _ _.5 _
use numbers 2-9 to fill in the blanks.
Answered by Claude Tardif. |
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A number pattern |
2006-10-02 |
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From Tim:
The patterns that went in 2s, 4s and 5s we got, but we are stuck on the pattern that doubles. We can't come up with the rule or equation that solves it.
With the first number being the term number and the second being the term, this is the pattern:
1-1
2-2
3-4
4-8
5-16
6-32
7-64
100-128
What is the rule for this?
Answered by Stephen La Rocque and Penny Nom. |
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A concrete foundation |
2006-10-02 |
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From A homeowner:
I am pouring a concrete foundation 8" X 14" X 23'. How many cubic feet of concrete do I need?
Answered by Penny Nom. |
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A proof by induction |
2006-10-02 |
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From Zamira:
i'm studying induction but i don't get how to proof that 1+2+2^2+2^3+...+2^(n-1) = (2^n) - 1.
Answered by Penny Nom. |
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Two word problems |
2006-10-02 |
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From Eve:
1. A surveyor's map shows a plan for the rectangular rose garden whose area is
a2+25ab-350b2. Find an algebraic expression for the length and width. If a=20 ft and b=10 feet, find the actual dimensions of the garden.
2.A square is enclosed in a circle. The area of the square is (4r2-32r+64)sq cm and the area of the circle is 484r2 sq cm. Write a polynomial in factored form to represent the difference of the two areas.
Answered by Stephen La Rocque. |
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The hypotenuse |
2006-10-02 |
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From Ashley:
How do you find the hypotenuse of a right triangle? I don't understand how to find c.
Answered by Stephen La Rocque. |
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The area of a circle |
2006-10-02 |
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From A student:
Calculate the area of a circle whose radius is 75 meters?
Answered by Stephen La Rocque. |
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The area of my hand |
2006-10-02 |
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From Waikiki:
is there a possible way for me to calculate the area of my hand (palm and fingers involved)? obviously it is curved and i can't find a way on how to solve it...
Answered by Chris Fisher and Diane Hanson. |
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What is 1.7142857143 as a fraction? |
2006-10-01 |
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From Lizzy:
What is 1.7142857143 as a fraction?
Answered by Stephen La Rocque and Penny Nom. |
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The focus of a parabola |
2006-10-01 |
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From Lily:
I have a mathematical assignment which includes applications of parabolas, hyperbolas and ellipses in the real world. I have been searching the internet and now I am ware that most of the applications of parabolas have a connection with what people call "the focus". However, I do not think I clearly understand what "the focus" of a parabola is. Would you please explain it to me?
Answered by Penny Nom. |
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Prove that 2nCn is less than 4n, for all positive integers n? |
2006-10-01 |
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From Anna:
How can I prove that 2nCn is less than 4n, for all positive integers n?
Answered by Penny Nom. |
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30+7(x-1)=3(2x+7) |
2006-09-29 |
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From Art:
30+7(x-1)=3(2x+7)
I know with the distributive law I multiply 7 by x and 7 by -1 and the same thing to the right, only 3 by 2 and 7 than I am lost?
Answered by Penny Nom. |
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