The composite figure shown above is composed of a semi-circle (colored red), a rectangle (colored blue), and an isosceles triangle (colored green). The longer side of the rectangle is three times the radius of the semi-circle. The altitude of the triangle is twice the radius of the semi-circle. If the area of the triangle is 20, find the area of this composite figure.
+37146 Area of triangle = 1/2 b h = 1/2 2r * 2r = 2r^2
2r^2 = 20
r^2 = 10
Area of rectangle 3r x 2r = 6 r^2 = 60
Area of semicircle 1/2 pi r^2 = = 5pi
Add the REDs for the total area
