Which of the following is a factor of both
x^2-2x-3 and x^2-5x-6?

answer choices:
a. x-3
b. x+3
c. x-1
d. x+1

X^2-2x-3

x^2+x-3x-3

x(x+1)-3(x+1)

(x-3)(x+1)

...

x^2-5x-6

x^2+x-6x-6

x(x+1)-6(x+1)

(x-6)(x+1)

So the common factor is (x+1)

X^2-2x-3 = (x - 3)(x + 1)
x^2-5x-6 = (x - 6)(x + 1)

answer
D.x+1