positive variables x,y,p,const;

equations mkt market clearing,
          supply defines y,
          demand defines x,
          rhs    Right Hand Side;

rhs..    const =e= 2;
supply.. y =g= p - const;
demand.. x =g= 1 - p;
mkt..    y =e= x;

model mkteql /rhs.const,supply.y,demand.x,mkt.p/;
solve mkteql using mcp;