Consider the given quadratic equation,
Here the coefficient of 'x' is positive, so the algebraic identity which will be used in the method of completing squares, is as follows,
Writing the left side of the given equation in the form of the left side expression of the identity,
It is observed that,
Note that, in order to complete the square, the left side expression requires a 'b-squared' term.
This can be done by adding the term to both sides of the equality.
Adding the term both sides,
Now, the left side of the expression perfectly fits the left side expression of the algebraic identity, which can be replaced by its right side term,
Taking square rootsboth sides,
Thus, the solutions of the given quadratic equations are,
Therefore, option C is the correct choice.