John Roy creates this drawing of a composite shape for an art contest. The area of the drawing is 78 square centimeters. What is the height of the rectangle?John Roy creates this drawing of a composite shape for an art contest. The area of the drawing is 78 square centimeters. What is the height of the rectangle?

Question

13
10
12
8

Answer 1

10

To find the height of the rectangle, we first need to find the width. Since the area of the drawing is 78 square centimeters and it is a composite shape, we can see that it consists of a rectangle and a triangle. Let's assume the width of the rectangle is x.

Area of rectangle = width * height
Area of triangle = (1/2) * base * height

So, x * height + (1/2)*x*height = 78
x * height + (1/2)*x*height = 78
x*height + 0.5*x*height = 78
x*height*(1+0.5) = 78
x*height*1.5 = 78
x*height = 78 / 1.5
x*height = 52
10 * height = 52
height = 52 / 10
height = 5.2

Therefore, the height of the rectangle is 10 centimeters.