Answer:
d+9
Explanation:
You cant combined unlike terms with addition
Step-by-step explanation:
sum implies addition
so you would add d and 9
since d is a variable the most you can simplify is
12h + 6k
3 times 4h = 12h
3 times 2k = 6k
312
3/4 × 32 = 24
9 × 32 = 288
288 +24=312