Question

Consider the following rectangle with a perimeter of 38ft. Find x Answer in units of feet.

Answer 1

X = 8

18-(2x8) = 18 - 16 = 2

8+9=17

Perimeter = 2x width + 2x length

Length = 2x2 = 4

Width = 2x17 =34 34 + 4 = 38

Answer 2

Let's turn this into an equation. Since we use 2L+2W=P to find the perimeter, we need to use that equation but fill in the information we know.

2(18-2x)+2(x+9)=38; let's distribute the parenthesis. 36-4x+2x+18=38; let's add like terms. 54-2x=38; let's subtract 54 from both sides. -2x=-16; divide both sides by -2. x=8 Let's check to make sure 8 is the correct answer. We need plug it in to both sides.

x+9=8+9=17; that's the length of one side, let's find the other. 18-2(x)=18-2(8)=18-16=2; that's the length of the other side.

17+17+2+2=34+4=38

So, x=8 ft.