Question

Subtract:

−2a + b + 6d from 5a − 2b − 3c

Answer 1

Change the sign of the term of the expression that is to be subtracted and then add.

Term to be subtracted = −2a + b + 6d
 Changing the sign of each term of the expression gives 2a-b-6d.
 On adding:
(5a − 2b -3c)+(2a-b-6d ) = 5a − 2b -3c +2a-b-6d
= (5+2)a+(− 2-1)b -3c -6d
= 7a − 3b-3c -6d