posted by trixie .
a high school wrestling mat must be square with 38-foot sides and contain two circles as shown. suppose the inner circle has a radius of "s" feet and the outer circle's radius is nine feet longer than the inner circle.
*write an expression for the area of the larger circle.
* write an expression for the area of the suqare outside the circle.
*use the expression to find the area if s=1.
If your question is so urgent, what have you done to try to solve these problems?
for the first star thing i got
a=3.14 x s^2+81
but i don't understand the other 2 bullets
* area of a circle is r^2 times pi
r=9s so r^2 is 9s^2. Multiply this by 3.14 to get the area of the circle. You can't actually solve it with a number since there is a variable involved.
* Area of a square is length times width
* If s=1, the area of the circle is 9^2 x 3.14. Take this answer and subtract it from the area of your square.
Hope this helps. Good luck!