17х-11х+5858=8912
17х-11х=8912-5858
6х=3054
х=3054:6
х=509
-0,6*(-2)^2-21-2*0,3=-2,4-21-2,6=-26
15х-14х+38+15х=990
28х+38=990
28х=990-38
28х=952
х=952:28
х=34
17 3/8-у=9 5/12+2,01
17 3/8-у=9 5/12+2 1/100
17 3/8-у=11 32/75
у= 17 3/8-11 32/75
у=(17-11)+3/8-32/75
у=6+3/8-32/75
у=6+225/600-256/600
у=5+569/600
у=5 569/600
Ответ: 5 569/600