Answer:
x = 8, or -11.
Explanation:
Given:
the given expression.

We need to solve the given expression by completing the square.
Solution:
Rewrite the expression as:

Whole expression divided by 2.

Where:

Solve the given expression by the following formula.
--------------(1)
Substitute b and c value in equation 1.






Add
both side of the equation.


Square root of the whole equation.

--------(1)
For positive sign.
Add
both side of the equation 1.




x = 8
Similarly for negative sign.
x = -11
Therefore, the value of x = 8, or -11.