Question 827911
You wrote the wrong equation.
You want {{{(x+5)/5-(2x-12)/7=1}}}


LCD 35.

{{{35(x+5)/5-35(2x-12)/7=35}}}
{{{7x+35-(10x-60)=35}}}
{{{-3x+95=35}}}
{{{-3x=35-95}}}
{{{-3x=-60}}}
{{{x=20}}}


You might have made a sign mistake, but not sure without seeing your actual work.