Question 926177
You should know how to read the slope directly from the equation and find intercept using the other variable assigned as 0.  You can also solve the equation for y, and then directly read the slope and y-intercept.  


{{{Ax+By=C}}}
{{{By=-Ax+C}}}
{{{y=-(A/B)x+C/B}}}, corresponding to the slope-intercept form, y=mx+b.
Slope is m;
y-intercept is b.


YOUR example:  {{{x+5y=15}}}
{{{5y=-x+15}}}
{{{y=-x/5+3}}},  OR if you prefer, {{{y=-(1/5)x+3}}}.


{{{graph(300,300,-6,6,-6,6,-x/5+3)}}}