Question

A rectangle has a perimeter of 42 ft its length, L, is 3 feet more than twice its width, W.

(c) Solve the system of equations that you just created by substitution to find the values of the length and width.​

Answer 1

Length of rectangle = 15 feet

Width of rectangle = 6 feet

Explanation:

Given:

Perimeter of rectangle = 42 ft

Length of rectangle = 2[Width of rectangle] + 3

Find:

Value of length and width

Assume:

Width of rectangle = w

SO,

Length of rectangle = 2[w] + 3

Perimeter of rectangle = 2[l + b]

42 = 2[2w + 3 + w]

2[3w + 3] = 42

6w + 6 = 42

6w = 42 - 6

6w = 36

w = 36 / 6

w = 6

So,

Width of rectangle = 6 feet

Length of rectangle = 2[w] + 3

Length of rectangle = 2[6] + 3

Length of rectangle = 12 + 3

Length of rectangle = 15 feet