Including the endpoints, how many points with two integer coordinates lie on the line joining (0,25) and (160,0)?
Slope = ( 0 - 25) / (160 - 0) = -25 /160 = -5/32
y changes by -5 units when x changes by 32
The number of integer coordinates = 1 + (160/5) = 1 + 32 = 33
