<span>(n/4-35)*6=150</span>
0.4(х-9)-0.3(х+2)=0.7
0.4х-3.6-0.3х-0.6=0.7
0.1х-4.2=0.7
0.1х=0.7+4.2
0.1х=4.9
х=4.9:0.1
х=49