Geometry

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Geometry

by vladmire » Tue Jan 20, 2009 4:17 pm
In this problem I need to find the area of the shaded portion in one problem. I know that the area of the square is A=s^2 or 4. The area of a circle is A=pi*r^2.

For the problem on the left side just the outside of the circle is shaded. I thought I could calculate the total area of circle and square and then subtract the area of square from total area of circle to get the area of shaded portion. I'm still lost thou can anyone help me with these?
Is the diameter 2sqrt2?
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shadedcircle.jpg
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by truplayer256 » Tue Jan 20, 2009 5:01 pm
Diameter is the diagonal of the square, so it's 2 sqrt 2 since you can the square into two 45-45-90 triangles..

Radius= 2 sqrt 2 divided by 2= sqrt 2
Area of circle: pi(r)^(2)=pi(sqrt2)^(2)=2pi

Area of shaded region= area of circle minus area of square---> 2pi-4