Question 727088
AREA=LW
AREA=4*7=28 M^2
28*2=(4+X)(7+X)
56=28+11X+X^2
X^2+11X+28-56=0
X^2+11X-28=0
{{{x = (-b +- sqrt( b^2-4*a*c ))/(2*a) }}} 
X=(-11+-SQRT(11^2-4*1*-28))/2*1
X=(-11+-SQRT(121+112))/2
X=(-11+-SQRT233)/2
X=(-11+-15.264)/2
X=(-11+15.264)/2
X=4.264/2
X=2.132 ANS. FOR THE SIDE INCREASE.
PROOF:
28*2=(4+2.132)(7+2.132)
56=6.132*9.132
56=56