Example1. Find the roots of Quadratic Equation x^2+10x-56=0 by the method of perfect square
Solution: x^2+10x-56=0
=>x^2+10x-56 = 0
Comparing the given equation with the standard quadratic equation ax^2+bx+c=0,
we get, a=1, b=10, c=-56.
:. Delta=b^2-4ac
=(10)^2-4 (1) (-56)
=100+224
=324
:. sqrt(Delta)=sqrt(324)=18
Now, alpha=(-b+sqrt(Delta))/(2a)
=(-(10)+18)/(2*1)
=8/2
=4
and, beta=(-b-sqrt(Delta))/(2a)
=(-(10)-18)/(2*1)
=-28/2
=-14
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