John Roy creates this drawing of a composite shape for an art contest. The area of the drawing is 78 cm² what is the height of the rectangle

In order to determine the height of the rectangle, we need to know the dimensions of the composite shape. Let's assume the rectangle has a length of L cm and a height of H cm, and the other shape (let's say a triangle) has a base of B cm and a height of H cm.

The area of a rectangle is calculated as A = L * H.
The area of a triangle is calculated as A = 0.5 * B * H.

Given that the total area is 78 cm², we can write:

78 = (L * H) + (0.5 * B * H).

Since we don't have the dimensions of the shapes, we cannot solve for the height of the rectangle.