l = 3 + 2w
2l + 2w = 48
Because we have a value for l we can plug it into the second equation to find the exact value of w.
2(3 + 2w) + 2w = 48
Distributive property.
6 + 4w + 2w = 48
Subtract 6 from both sides.
4w + 2w = 42
Combine like terms.
6w = 42
Divide both sides by 6.
w = 7
We can plug this value for w back into the original equation to find the value of l.
l = 3 + 2(7)
l = 3 + 14
l = 17