Answer:
The answer to your question is width = 3
Step-by-step explanation:
Data
width = w = ?
length = l = ?
Area = 15 units
Process
1.- Write equations to help to solve this problem
Area of a rectangle = width x length
= w x l Equation l
width = length - 2
w = l - 2 Equation ll
2.- Substitution
A = w x l
15 = (l - 2)(l)
3.- Expand
15 = l² - 2l
l² - 2l - 15 = 0
2.- Solve for l
-Find the prime factors of -15
15 3
5 5
1
15 = 3 x 5
3.- Factor l² -2l - 15 = 0
(l - 5)(l + 3) = 0
4.- Find the values of l
l₁ - 5 = 0 l₂ + 3 = 0
l₁ = 5 l₂ = -3
The length if the rectangle = 5, it could not be -3, because there are no negative lengths.
5.- Find w
w = l -2
w = 5 - 2
w = 3 units
