Question 1059386
{{{M=4D}}}
.
.
.
{{{(M-3)+(D-3)=39}}}
{{{M+D=45}}}
Substituting,
{{{4D+D=45}}}
{{{5D=45}}}
{{{D=9}}}
and
{{{M=4(9)}}}
{{{M=36}}}