Question

If using the method of completing the

square to solve the quadratic equation
x² + 5x + 10 = 0, which number would
have to be added to "complete the
square"?

Answer 1

25/4

Explanation:

x^2 +5x +10 =0

Subtract 10 from each side.

x^2 +5x = -10

To complete the square, take the coefficient of the x term.

5

Divide by 2

5/2

Then square it

(25/4)

Add this to each side

x^2 + 5x + 25/4 = -10 + 25/4

(x+5/2) ^2 = -15/4