26176:(y×56-46856)=409
y×56-46856=26176:409
y×56-46856=64
y×56 =64 + 46856
y×56 = 46920
y = 46920 : 56
у = 837,8
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(y+3698):507=630
y+3698=630 х 507
y+3698=319410
у = 319410 - 3698
у = 319041
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42172-5×x=7152
-5×x=7152- 42172
-5х = - 35020
х = - 35020: (-5)
х = 7004