5.4 Completing the Square

Completing the Square For quadratics in form: ax2 + bx + c where a = 1, we can use completing the square to solve. Find b/2 Find (b/2)2 Add (b/2)2 to both sides if it is a quadratic equation Add (b/2) inside the parenthesis

Completing the Square Helpful format: Example 1: x2 + bx + __(b/2)2__ = ( x + __b/2____) 2 Example 1: x2 – 6x Answer: x2 – 6x + 9 = (x – 3)2

Completing the Square Example 2: x2 + 15x Answer: x2 + 15x + (15/2)2 = (x + (15/2))2

Completing the Square Example 3: x2 + 6x – 16 = 0 Answer:

Completing the Square Example 4: x2 + 18x – 40 = 0 Answer: