The length of a rectangle is four times the width. The perimeter of the rectangle is 45 inches. Write a system of equations that represents this problem. What is the area of the rectangle​

Respuesta :

Step-by-step explanation:

2×length + 2×width = 45

length = 4×width

now, we are using the second equation (a variable identity) in the first equation

2×4×width + 2×width = 45

8×width + 2×width = 45

10×width = 45

width = 45/10 = 4.5 in

length = 4×width = 4×4.5 = 18 in

the area of the rectangle is

length × width = 18 × 4.5 = 81 in²