Completing The Square - 3 Examples

Now that you have learned how the completing the square formula is derived, we will go through three examples to help you apply the method step by step.

Example 1

Write the following equation in the form \(𝑎(𝑥+𝑏)^2+𝑐\)
  1. \(𝑥^2+4𝑥−6\)
  2. \(𝑥^2+5𝑥−6\)
  3. \(2𝑥^2+8𝑥+5\)
  4. \(4𝑥^2−8𝑥+6\)

Example 2

  1. Express \(𝑥^2+11𝑥−15\) in the form \((𝑥+𝑎)^2+𝑏\)
  2. Hence solve the equation \(𝑥^2+11𝑥−15=0\), giving your answers correct to two decimal places.

Example 3

  1. Express \(−𝑥^2+8𝑥+15 \) in the form \(a(𝑥+b)^2+c\)
  2. Hence solve the equation \(−𝑥^2+8𝑥+15=0\), giving your answers correct to two decimal places.
Share With Friends:
error:
Scroll to Top