Answer:
your equation is this... x2 - 100
since you have no x term to the first power you can write 0x... like this
x2 + 0x - 100
Now, what numbers will add to 0 and multiply to -100
The numbers 10 and -10 will
10 + -10 = 0
10 * -10 = -100
therefore
(x - 10)(x + 10) is the way you factor it
Explanation: