This video shows how to derive the quadratic formula by solving the quadratic equation.
This is a step by step solution starting with the quadratic equation.
1) divide through by the coefficient “a”
2) complete the square by adding “b^2/(4*a^2)” to both sides
3) subtract “c/a” from both sides of the equation
4) take the square root of both sides of the equation (don’t forget the plus or minus +/- in front of the square root.)
5) combine the fractions under the square root
6) subtract “b/a” from both sides of the equation
7) combine the fractions
We have successfully isolated “x” and therefore derived the quadratic formula from the quadratic equation.