Explanation:
px^2-qx+r
p(x^2-q/px)+r
p[(x^2-q/px +(q/2p)^2_(q/2p)^2)]+r
p[(x-q/2p)^2 -q^2/4p^2)]+r
p(x-q/2p)^2 -q^/4p+r
p(x-q/2p)^2-(q^2-4pr)/4p
9.4m questions
12.1m answers