Question 909913
80*60=4800 m^2
(80+x)*(60+x)=9600
x^2+140x+4800 = 9600
x^2+140x-4800 = 0
*[invoke quadratic "x", 1, 140, -4800] 
x=28.489

(80+28.489)*(60+28.489)=9600
(108.489)*(88.489)=9600
108.489*88.489=9600.083121