2l + 2w = 24
l = 3w - 4
Because we have a value for l, we can plug it into the first equation to solve for the exact value of w.
2(3w - 4) + 2w = 24
Distributive property.
6w - 8 + 2w = 24
Combine like terms.
8w - 8 = 24
Add 8 to both sides.
8w = 32
Divide both sides by 8.
w = 4
Now that we have a value for w, we can plug it into the second equation to solve for the exact value of l.
l = 3(4) - 4
l = 12 - 4
l = 8