1) 3a^2-a(3a-4b)-2(b-4a)= 3a^2-3a^2+4ab-2b+8a^2= 8a^2+4ab-2b
2)4(x-y)+7(x-y)=(x-y)(4+7)=11(x-y)=11x-11y
1) 3a^2-a(3a-4b)-2(b-4a)= 3a^2-3a^2+4ab-2b+8a^2= 8a^2+4ab-2b
2)4(x-y)+7(x-y)=(x-y)(4+7)=11(x-y)=11x-11y
1) 3a^2-a(3a-4b)-2(b-4a)= 3a^2-3a^2+4ab-2b+8a^2= 8a^2+4ab-2b
2)4(x-y)+7(x-y)=(x-y)(4+7)=11(x-y)=11x-11y