Find the sum or difference.
1. x-2+x+6
2. 2n-4n-3
3. 2(-3y-1)+(2y+7)
4. (6g-9)+1/3(15-9g)
5. (1-3k)-4(2+2.5k)
6. 1/2(2r+4)-1/4(16-8r)
7. you earn (4x+12) points after completing x levels of a video game then lose (2x-5) points. write an expression that represents the total number of points you have now.
factor the expression using the gcf.
8. 7+28
9. 25+50
10. 7b-7
11. 8a-16
12. 8x+12
13. 12y+34t
14. 10w+50z
15. 10v+12n
16. 9a+15b
factor out the coefficent of the variable.
17. 1/2a - 1/2
18. 1/4d - 3/4