Explanation:
1. 2+5x=4x+7
5x-4x=7-2
x=5
2. 4x-5=1+3x
4x-3x=1+5
x=6
3. 8-5x-4=-6x+6
-5x+6x=6-8+4
x=2
4. 4x+8+2x=5x-1
6x-5x=-1-8
x= -9
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