Question

Find the value of c that completes the square for the function f(x)= x2 + 4x + C.

Answer 1

Answer:

$= - 4 \times 2 + 4 \times ( - 4) + c \\ = - 8 - 16 + c \\ = 24 + c \\ \frac{ - c}{ - 1} = \frac{24}{ - 1} \\ c = - 24$