Question

A rectangle has a length of x and a with width 3 more than twice the length. A square has a side length of 3x. If both polygons have the same perimeter what is the value of x.

Answer 1

x = 1

Explanation:

Length of the rectangle = x

Width of the rectangle = 2x + 3

Side length of the square = 3x

Perimeter of the rectangle = 2(length + width)

= 2{x + (2x+3)}

= 2(x + 2x + 3)

= 2x + 4x + 6

= 6x + 6

Perimeter of a square = 4 * length

= 4 * 3x

= 12x

If both polygons have the same perimeter

Perimeter of the rectangle = Perimeter of a square

6x + 6 = 12x

6 = 12x - 6x

6 = 6x

x = 6/6

x = 1