Question 398269
(15+x)(30 + x) = 15*30 + 144
{{{450 + 45x + x^2  =594}}}
{{{x^2 + 45x - 144 = 0}}} ==> (x -3)(x + 48) = 0
==> x = 3, -48 ==> x = 3
==> Width is increased by (3/15)*100% = 20%, and the 
length is increased by (3/30)*100%  = 10%.