7x-(3+2x)=x+9
7x-3-2x=x+9
5x-3=x+9
5x-x=9+3
4x=12
x=12:4
x=3
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13-(2x-5)=x-3
13-2x+5=x-3
18-2x=x-3
x+2x=18+3
3x=21
x=21:3
x=7
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3x-(10-9x)=22x
3x-10+9x=22x
12x-10=22x
22x-12x=-10
10x=-10
x=-10:10
x=-1
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26-(17-2x)=5x
26-17+2x=5x
9+2x=5x
5x-2x=9
3x=9
x=9:3
x=3