What number must you add to complete the square? x^2 + 24x = 17

A.) 36

B.) 12

C.) 144

D.) 24

Complete the square: x^2 + 24x = 17

Identify the coefficient of x. It is 24. Take half of that coefficient: 24/2 = 12.

Now add the square of 12 to both sides of x^2 + 24x = 17

x^2 + 24x + 144 = 17 + 144

Write in factored form:

(x + 12) ^2 = 161

Taking the square root of both sides:

x+12 = plus or minus