Question 269255
y=mx+b  where m=slope and b= intercept
to find slope(m) of two points use the slope formula {{{m=(y2-y1)/(x2-x1)}}}
so for (8,-1)(4,3) x=(8,4)and y=(-1,3)
{{{m=((3)-(-1))/((4)-(8))}}} plug in the corresponding numbers
{{{m=(4)/(-4)}}} 
{{{m=-1}}} 
now we know the slope and what the x's and y's are so find b
{{{y=mx+b}}}
{{{-1=-1(8)+b}}}
{{{-1=-8+b}}}add 8 to both sides
{{{7=b}}} this is intercept
to check put in the other point with slope
{{{y=mx+b}}}
{{{3=-1(4)+b}}}
{{{3=-4+b}}}add 4 to both sides
{{{7=b}}}
this is correct because its the same number