mohon dibantu plisss mohon dibantu

1). jawabannya c

2).12x-3y+4x+4y
=12x+4x-3y+4y
=16x+y

3).(6x-5y-2z)+(-8x+6y+9z)
=6x-5y-2z-8x+6y+9z
=6x-8x-5y+6y-2z+9z
=-2x+y+7z

4).(6x-2y)-(7x-4y)
=6x-2y-7x+4y
=6x-7x-2y+4y
=-x+2y

5).(4+2m)( m-8)
=4m+32+2m²-16m
=2m²+4m-16m+32
=2m²-12m+32
smoga membantu