You meant to say x^2 - 49 and the second binomial is x^2 - 16.
x^2 - 49 = (x - 7) (x + 7).
Set each factor to 0 and solve for x individually.
x - 7 = 0
x = 7
x + 7 = 0
x = -7
Do the same for x^2 - 16.
Here is the set up:
x^2 - 16 = (x - 4) (x + 4).
Take it from here.
