Question

What is the value of the product (3 – 21)(3 + 2)?
5
9 + 4
9 - 41
13

Answer 1

Answer: -90

Explanation:

Correct answer is not shown in the choices?

FOIL method: 9 + 6 - 63 - 42 = -90

Easy method: (-18)(5) = -90

Answer 2

9 - 441

Explanation:

I think you are missing digits in the problem, and this is what you meant:

(3 – 21)(3 + 21) =

Of course, you can do the operations in the parentheses first.

= (-18)(24)

= -432

Maybe what the problem wants you to do is to use the product of a sum and a difference.

(a - b)(a + b) = a² - b²

(3 – 21)(3 + 21) =

= 3² - 21²

= 9 - 441