Perimeter is l+l+w+w, or l*2+w*2. We know the width is 4 feet. 26=4*2+l*2
So first, find what 4*2 equals. The answer is 8. So subtract 8 from both sides. 4*2 Cancels out, and 26 changes to 18. Then, divide both sides by 2. The (*2) gets cancelled and 18 becomes 9. The length is 9 FEET.
:)-Kibeye
