Answer:
Step-by-step explanation:
Let the length b y
Width = 2x - 3
Perimeter = 18x + 4
And
Perimeter = 2(l + w)
18x + 4 = 2(y + 2x - 3)
Dividing through by 2
9x + 2 = y + 2x - 3
Making y as subject
y = 9x - 2x + 2 + 3
y = 7x + 5
The missing side is 7x + 5
