Question

Which binomial is equivalent to (xy + z)(xy − z)?

Answer 1

x²y² - z²

Explanation:

Note that

(xy + z)(xy - z) are the factors of a difference of squares

a² - b² = (a + b)(a - b)

here a = xy and b = z, thus

(xy + z)(xy - z) = (xy)² - z² = x²y² - z²