Completing the Square
Completing the square is useful to change a quadratic equation from general form to vertex form.
General form ax2 + bx + c = 0 to vertex form a(x-h)2 +k = 0
Once we complete the square, it is easier to find the vertex in order to solve and graph the quadratic
equation.
The Process
1. x2 + 2x – 3 = 0
2. x2 + 8x +12 = 0
3. 2x2 + 12x + 7 = 0
4. 3x2 – 6x + 4 = 0
“You Try” Practice Problems
1. x2 – 2x – 8 = 0
2. x2 + 16x -22 = 0
3. 5x2 – 10x – 21 = 0
4. 4x2 + 16x – 65 = 0