Question 1202342
n nickels
d dimes
{{{n+d=34}}}
picking d as the single variable is a little more convenient than picking n.
{{{n=34-d}}}


{{{10d+5(34-d)=270}}}
-
{{{10d+5*34-5d=270}}}

{{{10d-5d=270-5*34}}}

{{{5d=270-5*34}}}

{{{d=(270-5*34)/5}}}

{{{highlight(d=20)}}}-----------and {{{highlight(n=14)}}}.