X^2+7x+6
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X^2+2x+1
(X^2+7x+6)/(X^2+2x+1)=(x+1)(x+6)/(x+1)²=(x+6)/(x+1)
D=b^2-4ac D=49-4*1*6 D=49-24=25=5^2 x1=(25-7)/2=9 x2=(-25-7)/2=-32/2=-16