The length of the flat screen tv is 5 inches less than 3 times it's width. If the perimeter of the tv is 150 inches, find the dimensions

AS we don't know the width so let consider width=x inches

According to given condition

length = (3x - 5) inches

TV screen is rectangular shaped so

Perimeter = 2 (length + width) = 2{ (3x-5) + (x) } equation 1

also given Perimeter = 150 inches equation 2

comparing equation 1 &2

2{ (3x-5) + (x) } = 150

2{3x-5+x} = 150

2{4x-5} = 150

8x-10 = 150

Adding 10 both sides

8x - 10 + 10 = 150+10

8x=160

dividing 8 both sides

8x/8 = 160 / 8

x = 20 inches width of screen.

length = (3x-5) = {3 (20) - 5}

=60-5

length = 55