3x-3=15 3x=15+3 3x=18 x=18/3 x=6
5x+10=20 5x=20-10 5x=10 x=10/5 x=2
4x-28=28 4x=28+28 4x=56 x=14
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72=8x-8 8x=72+8 8x=80 x=10
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6x-12=18 6x=18+12 6x=30 x=5
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46=16x-18 16x=46+18 16x=64 x=64/16 x=4