SOLUTION: I need a little help with this one please. Find a polynomial for the sum of the areas of three circles. The first circle has an unknown radius, the second one has a radius of 3, an
Algebra ->
Customizable Word Problem Solvers
-> Misc
-> SOLUTION: I need a little help with this one please. Find a polynomial for the sum of the areas of three circles. The first circle has an unknown radius, the second one has a radius of 3, an
Log On
Question 244876: I need a little help with this one please. Find a polynomial for the sum of the areas of three circles. The first circle has an unknown radius, the second one has a radius of 3, and the third a radius of 2. Help is greatly appreciated. Answer by Theo(13342) (Show Source):
You can put this solution on YOUR website! area of a circle is equal to pi * r^2 where pi is equal to is equal to 3.141592654 and r is the radius of the circle.
let A[i] = the area of circle i.
[] means sub as in A[i] means A sub i.
i can be 1, 2, or 3.
let S = A[1] + A[2] + A[3]
A[1] = pi * r[1]^2 because the radius is not known.
A[2] = pi * 3^2 because the radius is 3.
A[3] = pi * 2^2 because the radius is 2.
You get:
S = pi*r[1]^2 + pi*3^2 + pi*2^2
This becomes:
S = pi*r[1]^2 + pi*9 + pi*4
factor out the pi to get:
S = pi * (r[1]^2 + 9 + 4)
combine like terms to get:
S = pi * (r[1]^2 + 13)
I think that's your polynomial in its simplest form.
