Question

If using the method of completing the square to solve the quadratic equation

x2 + 11x + 30 = 0, which number would have to be added to "complete the
square"?

Answer 1

The number to add is (11/2)^2 = 121/4

Explanation:

Here, we want to know the number that will complete the square

We rewrite the equation as follows;

x^2 + 11x = -30

x^2 + 11x + (11/2)^2 = -30 + (11/2)^2

x^2 + 11x + 121/4 = -30 + 121/4