Answer:
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
