Complete the square for x^2 + x - 6.

First, let us separate the constant term and complete the square for (x^2 + 1x).
x^2 + x - 6 = (x^2 + x) - 6
Now, let us halve the coefficient of x.
0.5 of +1 = +0.5
Write (x )^2 with half the coefficient of x before the end bracket then subtract the square of half the coefficient of x.
(x^2 + x) - 6 = [(x + 0.5)^2 - 0.5^2] - 6 = (x + 0.5)^2 - 0.25 - 6 = (x + 0.5)^2 - 6.25,
which is the required completed square form (x + p)^2 + q.
Often, a GCSE question will ask what the minimum point of the graph is - and the minimum value of y is -6.25, and occurs when (x + 0.5)^2 = 0 so x=-0.5. Hence, the minimum point is (-0.5, -6.25).