Answer:
x = ± 10
Step-by-step explanation:
Given
y = x² - 100 ← a difference of squares , that is
y = x² - 10² = (x - 10)(x + 10)
To find the x- intercepts let y = 0 , that is
(x - 10)(x + 10) = 0
Equate each factor to zero and solve for x
x - 10 = 0 ⇒ x = 10
x + 10 = 0 ⇒ x = - 10
