subtract the following polynomials:

1.9x
7x

2.5x
4x

3.10x
7x

4.15x
15x

5.12x
13x

6.-x+y
x-y

7.4m
7m-2m²+5

8.a³-3a³+3a+1
-a³+3a²-3a+1

9.4x+3y-z
-x+8y+7z

10.-11a+8b+7c
-2b-5c


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