Question

what number must you add to complete the square?

x^2+4x=3

A. 8
B. 4
C. 2
D. 16

Answer 1

x^2+4x=3
x^2+4x-3=0
(a+b)^2=a^2+2ab+b^2
x^2+2*2*x-3=0
x^2+2*2*x+2^2-3-2^2=0
x^2+4x+4-3-4=0
(x+2)^2-7=0


we add 4 to complete the square

Answer 2

thanks