9+13у=35+26у
9с+2.65=36.85-9с
5=-1-(3-9х)
9-(8х-11)=12
12=(7х-9)-(11-х)
11х+103=1+(12х-31)

9+13у=35+26у9-35=26у-13у-26=13уу=-26:13у=-29с+2.65=36.85-9с9с+9с=36.85-2.6518с=34.2с=34.2:18с=1.95=-1-(3-9х)5=-1-3+9х5+3+1=9х9х=9х=9:9х=19-(8х-11)=129-8х+11=129+11-12=8х8х=8х=8:8х=112=(7х-9)-(11-х)12=7х-9-11+х12+11+9=8х8х=32х=32:8х=411х+103=1+(12х-31)11х+103=1+12х-31103-1+31=12х-11хх=103+30х=133