Question

The NYC Parks Department is designing a rectangular athletic field for a new park in Brooklyn. The width of the field needs to be 10 feet shorter than the length, and the perimeter of the field needs to be 80 feet. What is the length of the new field?

Answer 1

Length = 25feets

Explanation:

Let the length l = x

Width w = x - 10

Perimeter = 80

And Perimeter = 2(l + w)

:- 80 = 2{x + (x - 10)}

80 = 2{x + x - 10}

80 = 2(2x - 10)

80 = 4x - 20

4x = 80 + 20

4x = 100

x = 100/4

x = 25ft