Jawabanmu

2014-09-04T20:43:04+07:00
(13a-8b)+(12a+9b)=13a+12a-8b+9b
=15a+1b
(3m+4n-6)+(7n-8m+10)=3m-8m+4n+7n-6+10
-5m+11n+4
pengurangan:
a.(5x+3)-(x-1)=5x-x+3-(-1)
=5x-x+3+1=4x+4
b.(2y+15)-(4y-8)=2y-4y+15-8
=-2y+7