[tex]b)\\\\ -(3x+4)+2(5x-3)= - 3x-4 +10x-6=6x-10\\\\d)\\\\-5(2x+3)-3(5-3x)=-10x-15-15+9x=-x-30\\\\[/tex]
[tex]b)\\\\5(x-z)+2(z-x)=5 x-5z +2 z-2x=3x-3z\\\\c)\\\\2x^2(x-5)-3x(x^2-3x+5)=2x^3-10x^2-3 x^3+9x^2-15x=-x^3-x^2-15x\\\\d)\\\\6(a^2+c+ \frac{1}{3})-6(a^2- \frac{1}{2})-3(b+ \frac{1}{3})=6a^2+6c+2-6a^2+3-3b-1=-3b+6c +4[/tex]
