8х^2+4х+38=3х^2+5х+86

8х^2-3x^2+4x-5x+38-86=0
5x^2-x-48=0
D=1-4*5*(-48)=1+960=961
x1=(1+корень из961)/2*5=(1+31)/10=32/10=3,2
х2=(1-31)/10=-3