35,6+х=80-11,5
х=68,5-35,6
х=32,9
80-(35,6+32,90=11,5
11,5=11,5
--------------------------------------
х-8,5=21,77-9,15
х=12,62+8,5
х=21,12
9,15+(21,12-8,5)=21,77
21,77=21,77
----------------------------
50-х=8,132-7,16
х=50-0,972
х=49,028
(50-49,028)+7,16=8,132
8,132=8,132