Answer:
x= -4, 4
Explanation:
(x+3)(x-3)=7
FOIL
first x*x
outer x*-3 = -3x
inner 3*x = 3x
last 3*-3 = -9
add them together
x^2 -3x+3x -9 = x^2 -9
x^2-9 =7
add 9 to each side
x^2 -9+9 = 7+9
x^2 = 16
take the square root of each side
sqrt(x^2) = sqrt(16)
x = +- 4