The length of a rectangle is 2 1/2 times the width, and the perimeter is 42 feet. what are the dimensions of this rectangle? plz plz plz plz me i have been asking for 3 days

We know that the perimeter is 42 and the length is 2.5 the width, so we can create a system of equations

2l+2w=42

l=2.5w

Substitute l into the equation.

2(2.5w)+2w=42

5w+2w=42

7w=42

w=6

To solve for l, plug w into the second equation.

l=2.5(6)

l=15

Therefore, the width of the rectangle is 6 and the length of the rectangle is 15.

I hope this helped :)