11b+7b-15b+b=b(11+7-15+1)=4b
b=55
4b=4*50=200;
b=99
4b=4*99=396;
b=1001001
4b=4*1001001=4004004/
<span>-12х-3=11х-3</span>
<span>-12х-11х=-3+3</span>
<span>-23х=0</span>
<span>х=0</span>
<span> </span>