Question

Expand the polynomial: (−a+b)(b–a)

Answer 1

a² - 2ab + b²

Explanation:

(-a+b)(b-a)

(b-a)(b-a)

(b-a)²

b² - 2ab + a²

Or

a² - 2ab + b²

Answer 2

a^2 - 2ab + b^2

Explanation:

Step 1: Foil

(-a + b)(b - a)

(-a * b) + (-a * -a) + (b * b) + (b * -a)

-ab + a^2 + b^2 - ab

a^2 - 2ab + b^2

Answer: a^2 - 2ab + b^2