Question

David correctly factored the expression m^2 - ono

12m - 64.
Which expression did he write?
(1) (m-8)(m - 8) (3) (m - 16)(m + 4)
(2) (m - 8)(m + 8) (4) (m +16)(m - 4)
Explain why

Answer 1

the correct option is number (3). It corresponds with the expression David factorised.

Explanation:

David correctly factored the expression m² - 12m + 64, we want to check which one of the options he wrote.

(1) (m - 8)(m - 8) = (m - 8)²

= m² - 16m + 64

NOT THIS

(2) (m - 8)(m + 8) = m² - 8²

= m² - 64

NOT THIS

(3) (m - 16)(m + 4) = m² + 4m - 16m - 64

= m² - 12m - 64

THIS IS THE CORRECT OPTION AS IT CORRESPONDS WITH THE EXPRESSION DAVID FACTORISED

(4) (m + 16)(m - 4) = m² - 4m + 16m - 64

= m² + 12m - 64

NOT THIS