1) 2y - 6a – 12y +12a; 2) - (2 – a) – a + (2a + 1); 3) - 21(– y – 2k) + 2(– y + 3k); 4)...

Question

1) 2y - 6a – 12y +12a;

2) - (2 – a) – a + (2a + 1);

3) - 21(– y – 2k) + 2(– y + 3k);

4) 4x – (3 – 3(2x + 5)).

Answer 1

1)2y-6a-12y+12a=2y-12y-6a+12a=-10y=6a

2)-(2-a)-a+(2a+1)=-2+a-a+2a+1=2+2a+a-a=4a

3)-21(-y-2k)+2(-y+3k)=-21-y-2k+2-y+3k=-21+2-y-y-2k+3k=23-2y+1k

4)4x-(3-3(2x+5))=4x-(0(2x+5)=4x-0*2x+5=4x+x-0*5=5x-0