The length of a rectangle is nine inches less than twice the width. If the perimeter of the rectangle is 84 inches, find the dimension of the rectangle

L=25; W=17

Step-by-step explanation:

1. Create an equation

L+L+W+W=P -> (2w-9)+(2w-9)+(w)+(w)=84

2. Solve for W

    a) Collect like terms

(2w-9)+(2w-9)+(w)+(w)=84 -> 6w-18=84

    b) Move constant to the right

6w-18=84 -> 6w=102

    c) Divide by 6

6w=102 -> w=17

3. Now plug in W to the L

2w-9=L -> 2(17)-9=L

    a) Multiply

2x17=34 -> 34-9=L

    b) Subtract

34-9=25 -> 25=L

-22

times both sides by 2, times () by 8, add alile terms, move terms, add alike and caculate divide both sides by 3