Question 873712
Do you mean {{{c=1/5}}}?
It is correct but incomplete.
{{{c^2=1/25}}}
{{{c^2-1/25=0}}}
The difference of two squares,
{{{(c-1/5)(c+1/5)=0}}}
There are two solutions.
{{{c-1/5=0}}}
{{{c=1/5}}}
and
{{{c+1/5=0}}}
{{{c=-1/5}}}