Question 67792
CURRENT AREA=80*120=9600
TO INCREASE THIS AREA BY 20% IT MUST BE 9600*1.2=11520
THUS (80+X)(120+X)=11520
9600+120X+80X+X^2=11520
X^2+200X+9600-11520=0
X^2+200X-1920=0
USING THE QUADRATIC EQUATION WE GET
X=(-B+-SQRT[B^2-4AC])/2A
X=(-200+-SQRT[200*200-4*1*-1920])/2*1
X=(-200+-SQRT[40000+7680])/2
X=(-200+-SQRT47680])/2
X=(-200+-218.3578)/2
X=-200+218.3578)/2
X=18.3578/2
X=9.17875 ANSWER.