Question

Which expression is a factor of both x^2-9 and x^2+8x+15

Answer 1

Explanation:

• x^2-9=0
• x^2+8x+15=0

(x+5)(x+3)=0

x+5=0 or x+3=0

x=-5or x=-3

• x=-5 in x^2-9=0

(-5)^2-9=0

10-9=0

1=0

• x=-3 in x^2-9=0

(-3)^2-9=0

9-9=0

0=0