# The length of a rectangle is twice its width. If the diagonal measures 10 feet, then find the dimensions of the rectangle..

1
by marcguantero14

• Brainly User
2016-07-11T12:15:36+08:00
Use Pythagorean Theorem, where the diagonal is the hypotenuse.

The Pythagorean Theorem states that the square of hypotenuse (in this case, the diagonal) is equal to the sum of the squares of the two others sides.

Let hypotenuse (diagonal) = 10 ft.
Width = x
Length = 2x

Equation:

(2x)² + x² = 10²

4x² + x² = 100

5x² = 100

5x²/5 = 100/5

x² = 20

x =

x = +2   and   -2

Use the positive root for the dimensions.

The dimensions are:

Width: x = 2 ft.
Length: 2x = 2 (2)  or 4 ft.