Question

Solve by completing the square: x2 - 2x - 24 = 0
A. -4, -6
B. -4, 6
C. 4, -6
D. 4, 6

Answer 1

You can solve this in two ways
1. find the factors for $$(x^2-2x-24)$$
Or
2. substitute each given answer to the equation and find if it satisfies

Answer 2

x^2-2x+1-1-24=0
(x-1)^2-25=0
(x-1)^2=25
\[x-1=\pm \sqrt{25}\]

\[x=1\pm 5\]

x=6
x=-4

Answer 3

B