Let b= length and a=width Area= a*b and the problem said b=2a+3 (the length is 3ft more than double the width) Replace b into Area formula: Area= a*(2a+3) and we know that Area=77ft from the problem, so: 77=2a^2+3a now order and equal to zero: 2a^2+3a=77 now solve this with quadratic formula and you will get so values for a: -7ft and 5.5ft as you know the dimensions could not be negative so the correct answer for "a" side is 5.5ft, for getting the b side you haeve to replace a=5.5 into b=2a+3 and you will get b=2*5.5+3= 14ft. Finished.
