What is the value of the product (3-21) (3 + 21) ?

Multiply the two brackets together

(3-21) (3+21)

(3) (3) (3) (+21) (-21) (3) (-21*21)

9+63-63-441

- 441 because whenever multiplying a - negative number and a + positive number = - negative number

9-441

= - 432

Answer: - 432