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. Related Lessons: iGCSE3 Complete The SquareiGCSE3 Sketch Quadratic Graph Example 1 Write the following equation in the form \(𝑎(𝑥+𝑏)^2+𝑐\) \(𝑥^2+4𝑥−6\) \(𝑥^2+5𝑥−6\) \(2𝑥^2+8𝑥+5\) \(4𝑥^2−8𝑥+6\) Example 2 Express \(𝑥^2+11𝑥−15\) in the form \((𝑥+𝑎)^2+𝑏\)Hence solve the equation \(𝑥^2+11𝑥−15=0\), giving your answers correct to two decimal places. Example 3 Express \(−𝑥^2+8𝑥+15 \) in the form \(a(𝑥+b)^2+c\) Hence solve the equation \(−𝑥^2+8𝑥+15=0\), giving your answers correct to two decimal places. Share With Friends: Related Lessons: iGCSE3 Complete The Square iGCSE3 Sketch Quadratic Graph