Question

-) Factorise m-4m - 21 and find the value of the expression if
(i) m = 7 and (ii) m = -3​

Answer 1

m-4m-21, m= 7

7-4(7) -21

7-28-21

7-49

-42

m-4m-21, m= -3

(-3) -4(-3) -21

(-3) +21-21

(-3) +0

-3