ada di buku mtk kls 8 hal 49 latihan 2.2 kurikulum 2013 terima kasih

1. (13a-8b)+(12a+9b)
    = 13a -8b+12a+9b
    =13a +12a-8b+9b
    =25a+b  
2. (15i+14b+13k)+(-30i-45j+51k)
    = 15i+14b+13k-30i-45j+51k
    =51i-30i+14b+13k-  51k+45j
    =  -15i+14b-38k+45j
3.(3-17x+35z)+(4x +23y-9)
    =3-17x+35z+4x+23y-9
     =3-9-17x+4x+35z+23y
       = -6-13x+35z+23y
4. (42n+35m+7) - (50m-20n+9)
     =42n+35m+7-50m+20n-9
      = 42n +20n+35m-50m +7- 9
     =62n-15m-2
5. (5x+3)-(x-1)
     =5x+3-x+1
     =5x-x+3+1
     =4x+4
6.  (2y+15z)-(4y-8)
     =2y+15z-4y+8
     =2y-4y+15z+8
     =-2y+15z+8
7.  5z+3-(2z-7)
     =5z-2z+3+7
      =3z+10
8. x-y-(6x+4)
    = x-y-6x-4
    =x-6x-y-4
    =-5x-y-4
9. a.  2a+2a+2a+2a=8a
    b.  3a+3b+3a+3b=6a+6b
    c.  a+b+c+d+(b-d)+(a-c)=2a+2b