The Jones family bought a new pet rabbit. They want to build an enclosure outside . They have 30ft of lumber. Find the length and width of the enclosure if the length is to be 4ft longer than twice the width.

L = 2W + 4

2L + 2W = 30

Substitute 2W+4 for L in second equation and solve for W. Insert that value into the first equation and solve for L. Check by inserting both values into the second equation.