2:D

3:D

4:D

5:4b negative 5/6 m quadratic n quadratic

6:-a +b-c

7:2x？ -x+ 1

8:-3/ 1

9:-ab (7th power)

10: 1 1y-92a-x- 1-32x- 1 1- 13x？ + 10x- 1 a？ +5a+4

1 1:B

12:B

13:45

14: 15XY-6X-9 Y=0.4

2A？ -ab+ 17b？

17:a-(2/ 1a-2)-[3/2(2/ 1)+ 1]+6/ 1a-3/ 1 3/299

18:a+3.5 Original formula =-24

Give points! ! ! ! ! ! ! ! !