Question

What number must you add to complete the square

x^2+x

A. 1/2
B. 2
C. 1/4
D. 1

Answer 1

for
`ax^2+bx+c`

when a=1, then the value of c that will make the quadratic a perfect square (allows you to complete the square) is
`((b)/(2))^2`

given x^2+x

b=1

so
`c=((1)/(2))^2=(1)/(4)`

answer is C