Sagot :
Answer:
3a
Step-by-step explanation:
first:
simplify the same signs
7a+8a=15a
second:
minus the remaining terms
15a-12a=3a
Answer:
3a
Step-by-step explanation:
first:
simplify the same signs
7a+8a=15a
second:
minus the remaining terms
15a-12a=3a