# sir please explain method of completing the square with illustrated example.

### Asked by mandal.sunny88 | 29th Jul, 2016, 12:32: AM

###
Any quadratic equation can be converted to the form (*x + a*)^{2 }- *b*^{2} = 0 by adding and subtracting some terms. This method of finding the roots of quadratic equation is called the method of completing the square.

The steps involved in solving a quadratic equation by completing the square, are as follows::

**Step 1**: Make the coefficient of x^{2} unity.

**Step 2**: Express the coefficient of x in the form (2)(x)(p)

**Step 3**: Add and subtract the square of *p*.

**Step 4**: Use the square identity (*a + b*)^{2} or (*a - b*)^{2} to obtain the quadratic equation in the required form (*x + a*)^{2 }- *b*^{2} = 0. Then, take the constant term to the other side of the equation.

**Step 5**: Take the square root of the obtained equation to get the roots of the given quadratic equation.

Any quadratic equation can be converted to the form (*x + a*)^{2 }- *b*^{2} = 0 by adding and subtracting some terms. This method of finding the roots of quadratic equation is called the method of completing the square.

The steps involved in solving a quadratic equation by completing the square, are as follows::

**Step 1**: Make the coefficient of x^{2} unity.

**Step 2**: Express the coefficient of x in the form (2)(x)(p)

**Step 3**: Add and subtract the square of *p*.

**Step 4**: Use the square identity (*a + b*)^{2} or (*a - b*)^{2} to obtain the quadratic equation in the required form (*x + a*)^{2 }- *b*^{2} = 0. Then, take the constant term to the other side of the equation.

**Step 5**: Take the square root of the obtained equation to get the roots of the given quadratic equation.

### Answered by Rashmi Khot | 29th Jul, 2016, 10:11: AM

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