Answer: The answers are provided below
Step-by-step explanation:
15. 7c + 8d + 2c + 17d
= 7c + 2c + 8d + 17d
= 9c + 25d
16. 4(2m - 3p) + 12m + 7p
= 8m - 12p + 12m + 7p
= 8m + 12m -12p + 7p
= 20m - 5p
17. (15j +9z) - (12j + 6z)
= 15j - 12j + 9z + 6x
= 3j + 15z
18. 3y + 6.7x + y + 2.3x +10 - 7
= 6.7x + 2.3x + 3y + y + 10 - 7
= 9x + 4y + 3
19. 2b + (-6c) +5e - 11b + e+ 6c
= 2b - 11b - 6c + 6c + 5e + e
= -9b + 6e