Jawabanmu

2014-08-15T15:59:58+07:00
5(4a+2b)+3(5b-7a+8)
= 20a+10b+15b-21a+8
= -a+25b+8

2014-08-15T16:31:44+07:00
20a + 10b + 15b - 21a + 24
-a + 25b + 24