(12_5/13+у)-9_9/13=7_7/13
12_5/13+у=7_7/13+9_913
12_5/13+у=17_3/13
у=17_3/13-12_5/13
у= 4_11/13
23 16 24 63 4м 5 дм 8дм4см 100 1ч 8 мин
На 100см
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123,132,213,231,312,321
2) 213,231,321
3) 132<231
180-90=90
<span>90:2=45 ° !!!!!!!!!!!!!!!!!!!!!</span>