tolong dong di jawab besok di kumpul

semoga membantu yaaaaaa

3.a(42n+35m+7)-(-50m-20n+9)
=42n+35m+7-(-20n-50m+9)
=42n+35m+7+20n+50m-9
=42n+20n+35m+50m+7-9
=62n+85m-2
b. (5x+3)-(x-1)
=5x+3-x+1
=5x-x+3+1
=4x+4
c. (2y+15z)-(4y-8)
=2y+15-4y+8
=2y-4y+15+8
=-2y+23

4.5z+3-(2z-7)
=5z-2z+3+7
=3z+10

5.6x+4y-(x-y)
=6x-x+4y+y
=5x+5y

6.a.5x-9-(7x+15y)
=5x-7x-9-15y
=-2x-9-15y
b. 5x-3y+7-(5y-3x-4)
=5x+3x-3y-5y+7+4
=8x-8y+11
c. - x^2-6xy+3y^2-<5x^