The perimeter of a rectangle is 18x – 24 and the width is
2x – 9. What is the length?
A: -7x + 3
B: 16x + 15
C: 7x - 3
D: 7x + 3

C

Step-by-step explanation:

18x - 24 = 2 [length + 2x - 9]

9x - 12 = length + 2x - 9

Length = 7x - 3

C: 7x - 3

Step-by-step explanation:

The perimeter of a rectangle is  given by

P = 2(l+w) where l is the length and w is the width

We know the perimeter is 18x -24 and the width is 2x-9.  Substituting these values into the equation

18x-24 = 2( l+2x-9)

Divide each side by 2

(18x-24)/2 = 2/2( l+2x-9)

9x-12 = l+2x-9

Add 9 to each side

9x-12 +9 = l+2x-9+9

9x -3 = l+2x

Subtract 2x from each side

9x-2x-3 = l+2x-2x

7x -3 = l

The length is 7x-3

the third picture

step-by-step explanation: