Question

5. The area of a triangle is equal to that of a square whose side measures 60 inches. Find the side of
the triangle whose corresponding altitude is 90 inches.

Answer 1

The side length of the square is 60 inches. The area is therefore 60 x 60 = 3600 square inches.

We need to find the base of the triangle such that it too, given an altitude of 90 inches, will have an area of 3600 square inches.

We have\[3600=\frac{1}{2}bh=\frac{1}{2}b(90)=45b\]That is\[b=\frac{3600}{45}=80\]inches.