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	multiply = 3a - 3b by a+b		2008-07-15
		From chaleen: multiply = 3a - 3b by a+b Answered by Penny Nom.
	How much sand do I order?		2008-07-15
		From jackson: We would like to put 2 inches of sand down. The pool is 24 feet. How much sand will we need? The person we spoke to yesterday was talking in tons, but on these sites it is talking cubic yards or feet. Please help. We would like to get the sand ordered so we can get the pool up! Answered by Harley Weston.
	The length of an arc		2008-07-14
		From Chris: trying to find the length of an arc or segment of a circle when the radius or circumference is unknown take a circle, put a line across the circle label it A /B /C A and C are the end points, B is the middle line length is 86. From B to the side of circle is 16. Label that point D need to find the length of A D C Answered by Penny Nom.
	A trig exercise		2008-07-14
		From Carter: let cos B = a, find cos 2B and sin 2B in terms of a and hence confirm that cos^2 (2B) + sin^2 (2B) = 1 Answered by Harley Weston.
	n choose r equals n-1 choose r plus n-1 choose r - 1		2008-07-14
		From fae: Prove that ( n ) = ( n – 1) + ( n - 1 ) ( r )         ( r )        (r-1) NOTE: the ( ) should be one for n taken r and so on. but there is no one big ( ) that will cater two lines Answered by Janice Cotcher.
	A reflected line segment		2008-07-14
		From Peter: Segment AB has endpoints A(-1,2) and (3,1). Segment AB is reflected over the y-axis such that A becomes A' and B becomes B'. What is the positive difference between the lengths of segment AA' and segment BB'? Answered by Janice Cotcher.
	A silo with a flat side		2008-07-14
		From Amy: Without using the Pythagorean Theorem, determine the capacity of a silo in cubic feet of grain if: the cylinder-shaped silo has one flat, rectangular face that rests against the side of the barn; the height of the silo is 30 feet and the face resting against the barn is 10 feet wide; the barn is approximately 5 feet from the center of the silo. Answered by Harley Weston.
	Like terms		2008-07-14
		From Jana: Hello, i am a student in year 8 doing Algebra. My Teacher is doing a sheet with us and it asks us to find Like Terms. The Questions have sentences and you have to find the Like Term. I was wondering, does it matter when there is numbers that are different? are they still like terms? I'm really confused, i'll write out an example of the questions, so you know what i mean. It says to find the like terms: (1.) c- 3c + 7c (2.) 4x - 7x + 5x (3.) 3xy + 4 xy Answered by Penny Nom.
	Express as a function of x		2008-07-14
		From Rita: Express the area A of an isosceles right triangle as a function of x of one of the two equal sides. NOTE: I always see the phrase "Express as a function of x" in math textbooks. What exactly does that phrase mean? I also have seen it written as "Express in terms of x." Answered by Penny Nom.
	The area of a triangle - no height given		2008-07-12
		From phoenix: given triangle with angles 30,105 45 degrees. base = 2radical 2, no height given Answered by Penny Nom.
	Chords and arcs		2008-07-11
		From Ronnie: We are trying to build a semi life size ark decoration , and we are trying to cut the sides out . The curved sides and we can't figure our radius , all we know is that our chord length is 24ft. any suggestions on how to find the radius or maybe even the arc length or circumference or diameter? Answered by Harley Weston.
	A Falling Rock		2008-07-11
		From Rita: This question has 3 parts. If a rock falls from a height of 20 meters on the planet Jupiter, its height H (in meters) after x seconds is about H(x) = 20 - 13x^2 (a) What is the height of the rock when x = 1.2 seconds? (b) When is the height of the rock 15 meters? (c) When does the rock strike the ground? Thank you Answered by Janice Cotcher.
	Domain & Range of a Periodic Function		2008-07-11
		From Michelle: The depth, w metres, of water in a lake can be modelled by the function, w=5sin(31.5n+63) +12 where n is the number of months since January 1, 1995. Identify and explain the restrictions on the domain and range of this function. Answered by Janice Cotcher.
	Mathematical induction		2008-07-11
		From lyn: can you give me a basic example of a mathematical induction Answered by Harley Weston.
	A difference quotient		2008-07-10
		From Rita: Find the difference quotient of f, that is, find [f (x + h) - f (x)]/h, where h does not = 0 for the given function. Be sure to simplify. f(x) = 1/(x + 3) Answered by Janice Cotcher.

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