




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



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



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7у+у+27=99
8y+27=99
8y=99-27
8y=72
y=72 / 8
y=9
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42х-28х+180=600
14x+180=600
14x=600-180
14x=420
x=420 / 14
x=30
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15х-х-16=82
14x-16=82
14x=82+16
14x=98
x=98/ 14
x=7
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8х+14=870
8x=870-14
8x=856
x=856 / 8
x=107