Question

Solve the quadratic equation y^2-5y=-4 by factoring.

Answer 1

$y^2-5y=-4\\ y^2-5y+4=0\\ y^2-y-4y+4=0\\ y(y-1)+4(y-1)=0\\ (y+4)(y-1)=0\\ y=-4 \vee y=1$