Question 280987
(11-2x)(14-2x)=80
154-28x-22x+4x^2=80
4x^2-50x+154-80=0
4x^2-50x+74=0
{{{x = (-b +- sqrt( b^2-4*a*c ))/(2*a) }}} 
x=(50+-sqrt[-50^2-4*4*74])/2*4
x=(50+-sqrt[2,500-1,184])/8
x=(50+-sqrt1,316)/8
x=(50+-36.277)/8
x=86.277/8
x=10.784 ans.
x=(50-36.277)/8
x=13.723/8
x=1,7154 ans.