Question 9 of 15 For which of the following equations are x = 3 x=3 and x = - 3 x=-3 both solutions? (The 2s next to the x are x to the power of 2 int the choice)

A) x2-3x-9=0

B) x2+9=0

C) x2+6x-9=0

D) x2-9=0

For option D, x²-9,

if you apply the identity[ (a²-b²) = (a+b) (a-b) ] it will give you (x+3) (x-3) = 0,

here two things are possible if (x-3) is the zero, 3 I. e. x=3, then the equation is true

or

(x+3) is 0, I. e. x=-3.

And rest of the equation don't have real roots!