so use y=mx+b m=slope or rise/run b=y intercept where line passes throught y axis or when x=0
to find slope, do (y1-y1)/(x1-x2) (x,y) (3-9)/(-1-(-5))=(-6)/(-1+5)=(-6)/(4)=-3/2 y=-3/2x+b solve for b by subsituting 3=x -1=y -1=-3/2 times 3+b -1=-9/2+b Add -9/2 to both sides -1=-2/2 -2/2+9/2=7/2 7/2=b
