slope=rise/run
we see that the slope will be negative
it is more accurate the farther we are apart
we wiill use the points closest to the line, those are (3.5,3.5) and (5,1)
slope between (x1,y1) and (x2,y2) is (y2-y1)/(x2-x1)
for this one
(1-3.5)/(5-3.5)=-2.5/1.5=-1.666666666≈-1.67
the slope is -1.67