Kristine has a bedroom wall that is shaped like a trapezoid with a height of 9 ft, a top base of 12 ft, and a bottom base of 15 ft. In the middle of this wall is a circular window whose radius is 3 ft.
First, we figure out the area of the wall, which is shaped like a trapezoid. The equation for the area of a trapezoid is [tex] \frac{1}{2} (a+b)h[/tex] where a is the top base, b is the bottom base and h is the height. Substitute your given values into the equation and solve: A=1/2(12+15)9 A=4.5(27) Area of the wall= 121.5ft²
Now we figure out the area of the of the circular window. The formula for the area of a circle is [tex] \pi r^{2} [/tex] where r is the radius Substitute your given values into the equation and solve: pi×3² [tex]9 \pi =28.27433388 ft^{2} [/tex]
Now finally minus the area of the window from the area of the wall. 121.5-28.27433388=93.22566612 To 1 d.p., the area of the wall without the window is 93.2ft²
