Suppose you know the base of a rectangle has a length of 3 inches and a diagonal has a length of 5 inches. Find the area of the rectangle.

Answer 1

Since we have a rectangle, that means that we have 90 degree angles. That in turn means we can use the Pythagorean Theorem to solve for height:

3² + b² = 5²

9 + b² = 25

b² = 16

√b² = √16

b = 4

Now that we have a length and width, we can find the area:

A = Lw

A = 3 in * 4 in

A = 12 in²