Question 469129
{{{M=R1L-F(L-x)}}}
{{{M=R1L-FL+Fx)}}}
{{{M-Fx=R1L-FL)}}}
{{{R1L-FL=M-Fx)}}}
{{{L(R1-F)=M-Fx)}}} divide by {{{(R1-F)}}}
{{{L=(M-Fx)/(R1-F))}}}