✔ 最佳答案
= (h + 9) + (3h - 8)
= h + 9 + 3h - 8
= 4h +1 .. just add like terms
Edit: I already answered the question correctly so why did 3 other people write out the exact same thing? Why not just give me a thumbs up? I never understand this about the math section of Y!A.