1.2X-10.3x=-8.3x
2.3X-X-5X=-3x
3.-b+0.6b-2.6b=-3b
4.m-n(2次方)+m-n(2次方)=2m-2n²
5.2(4X-0.5)=8x-1
6.-3(1-1/6x)=x/2-3
7.-X+(2X-2)-(3X+5)=-x+2x-2-3x-5=-2x-7
8.3A⑵+A⑵-(2A⑵-2A)+(3A-A⑵)
=3A²+A²-2A²+2A+3A-A²
=A²+5A
9.(5a+4c+7b)+(5c-3b-6a)
=5a+4c+7b+5c-3b-6a
=-a+4b=9c
10.(8xy-2[二次方]+Y【二次方】-(x【二次方】-Y【二次方】+8xy)
=8xy-2²+y²-x²+y²-8xy
=2y²-x²-4
11 .(2【二次方】-1/2+3X)-4(X-X【二次方】+1/2)
=2²-1/2+3x-4x+4x²-2
=4x²-x+3/2
12.3X【二次方】-[7X-(4X-3)-2X【二次方】]
=3x²-7x+4x-3+2x²
=5x²-3x-3