5(x-z)-2(x+z)=5x+5z-2x-2z=3x+3z=3(x+z)
2(2r-3s)-3(r-2s)=4r-6s-3r+6s=r
6(2a+c)+2(6a-c)-4c=12a+6c+12a-2c-4c=24a
3(x-1)+(x-2)-x=3x-3+x-2-x=3x-5
5n-3(n+2)+(n-6)=5n-3n-6+n-6=3n-12=3(n-4)
m-(2m-6)+3(m-3)=m-2m+6+3m-9=2m-3
2(3x+1)-(x-2)-3x=6x+2-x+2-3x=2x+4=2(x+2)