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A quadratic equation is of the form ax^{2}+ bx + c = 0 and we can solve this equation by various methods. One of the methods to solve a quadratic equation is by ‘Completing the square’. Complete the square calculator is the online tool which can complete the square instantly.

**Example 1: Solve by completing the square: x**^{2}** + 6x -7 = 0**

Check whether the co-efficient of x^{2} is 1. Yes!

Add ‘7’ on both sides! ?** x**^{2}**+6x = 7**

Now divide the coefficient of ‘x’ by ‘2’? 6/2 = 3

Now square the number got from the previous step ? 3^{2} = 9

Add the above ‘9’ on both sides ? x^{2}+6x+9=7+9** ****?**** x**^{2}**+6x+9 = 16**

Now x^{2}+6x+9 can be factored as (x+3) (x+3) = (x+3)^{2}

(x+3)^{2} = 16 ?x+3 = √16

x+3 = +- 4?x = -3 +-4

**x = 1 and x= -7**

**Example 2: Solve by completing the square: x**^{2}** + 4x – 8 = 0**

Check whether the co-efficient of x^{2} is 1. Yes!

Add ‘8’ on both sides! ?** x**^{2}**+4x = 8**

Now divide the coefficient of ‘x’ by ‘2’? 4/2 = 2

Now square the number got from the previous step ? 2^{2} = 4

Add the above ‘4’ on both sides ? x^{2}+4x+4 = 8+4** ****?**** x**^{2}**+4x+4 = 12**

Now x^{2} + 4x + 4 can be factored as (x+2) (x+2) = (x+2)^{2}

(x+2)^{2} = 12 ?x+2 = √12

**x = -2 + 2√3 and x = x = -2 - 2√3**