Write an expression to model the perimeter of the rectangle. length is x-9 and width is 3x-4. part b the perimeter of the rectangle is 138. what is x. plzz i will give you 100 points

Step-by-step explanation:

To find the perimeter of something, we add all of the measurements of the sides together.

A rectangle has 4 sides, this means we must double the algebraic hints given to us.

If we add them all up together it will look like this:

x-9+x-9+3x-4+3x-4=138

If we simplify it by collecting the like terms:

8x-26=138

We add 26 onto 138

8x=164

To find out what x equals, we divide by 8:

164÷8= 20.5

x=20.5cm

x-9 is 11.5

3x-4 is 57.5

I know that you will not give 100 points but just wanted to help.

A: P = 8x - 26

B: x = 20.5

Step-by-step explanation:

Part A

Equation

P = 2*(L + W)

Givens

Solution

Part B

Given

P = 138

Equation

P = 8x - 26

Solution

b

step-by-step explanation: