Step (i) Divide each side by a which is 4 (so that the coefficient of the x² is 1)

Step (ii) Rewrite the equation with the constant term (ie. 'c') on the right side.

[No need in this example]

Step (iii) Complete the square by adding the square of one-half of the coefficient of x to both sides ie. .

Step (iv) Write the left side as a square and simplify the right side.

Step (v) Equate and solve

So

or

This gives or x = -1