5x+35=140-2x
5x+2x=140-35
7x=105
x=15
9x-27=70+4x
9x-4x=70+27
5x=97
x=97/5
12+7x=2x+32
7x-2x=32-12
5x=20
x=4
250/X+25=75
250/x=75-25
250=50x
x=5
23X-72X+5=64
-49x=59
x=-59/49
4X+25=9X-15
5x=40
x=8
47+X-2X+4=68
47+4-68=2x-x
x=-17