How To Solve Quadratic Equation By Completing The Square

Recall that if we have a quadratic equation of the type $x^2=a$ (where $a>0$ ) then the solutions are $x=\pm \sqrt{a}$ .

Now for the general quadratic equation $ax^2+bx+c=0$ we can transform this equation by completing the square into equation of the form $(x+p)^2=q$ . If we think of x+p as one single variable $z$ , then we have $z^2=q$ and this equation is similar to the previous one which we know how to solve it.

The videos below will give you some examples how to do this sort of transformation practically and solve the quadratic equation.