Question

If using the method of completing the square to solve the quadratic equation x^2+8x+11=0, which number would have to be added to "complete the square"?

Answer 1

4

Explanation:

x²+8x+11=0

x²+8x+(+4)²-(+4)²+11=0

Answer 2

16

Explanation:

x2+8x= −11−11

28​=4→(4)2=16

x2+8x+16=x2+8x+16= −11+16−11+16

(x+4)2= 55

16