Question 330041
{{{1/3 -k+(3/6)k = (1/3)k - k-(1/2)k}}}
{{{1/3-1/2k=(2/6)k-(6/6)k-(3/6)k}}}
{{{1/3-(3/6)k=-(7/6)k}}}
{{{1/3=-(4/6)k}}}
{{{k=-(6/4)(1/3)=-1/2}}}