6x^2+7x=5

x(x-5)=1-4x

D=49+4*6*5=169X1=(-7+13)/12=0,5X2=(-7-13)/12=20/12=1 2/3X^2-5x-1+4x=0X^2-x-1=0D=1+4*1*2=9X1=(5+3)/4=2X2=(5-3)/4=0,5