Question

Please help me work this problem

Answer 1

13a

Explanation:

Given

9a + 3a + a ← are like terms, they all have the variable a

To simplify add the numeric parts of the terms, that is

= (9 + 3 + 1 )a ← note a has a coefficient of 1

= 13a

Answer 2

13a

Explanation:

9a + 3a + a = 13a