3452-х=768+987
х=3452-768-987
х=1697
---
х / 4 = 195
х=195*4
х=780
---
х-516=360 / 90
х=4+516
х=520
---
2170-(n+990)=1090
2170-n-990=1090
n=2170-990-1090
n=90
---
у / 30 = 4085+2365
у=6450*30
у=193500
---
518-у=144+212
у=518-144-212
у=162
---
164 / у = 345-304
у=164/41
у=4
---
728+(t-308)=1420
728+t-308=1420
t=1420-728+308
t=1000
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