the equationi of a line that passes through (x1,y1) and has a slope of m is
y-y1=m(x-x1)
find slope
slope between points (x1,y1) and (x2,y2) is
(y2-y1)/(x2-x1)
given
(2,-5) and (-1,1)
slope=(1-(-5))/(-1-2)=(1+5)/(-3)=6/(-3)=-2
a point is (-1,1)
y-1=-2(x-(-1))
y-1=-2(x+1)
slope intercept is solve for y
y-1=-2(x+1)
y-1=-2x-2
add 1
y=-2x-1
