A) two ordered pairs: (51,3) and (59,5)
y=mx+b
m= vertical change / horizontal = 5-3 / 59 - 51 = 2/8 = 1/4 = 0.25
y=0.25x+b
51=0.25*3+b
b=51-0.75
b=50.25
y=0.25x+50.25
where y = speed, x = time
b) we have 2 poits (51,3) and (59,5) so there is no problem to sketch the graphy passing though those points :)