Check if x(x + 1) + 8 = (x + 2) (x – 2) is in the form of quadratic equation.

Solution

Given,
x(x + 1) + 8 = (x + 2) (x – 2)
x²+x+8 = x²-2² [By algebraic identities]
Cancel x² both the sides.
x+8=-4
x+12=0
Since, this expression is not in the form of ax²+bx+c, hence it is not a quadratic equation.