1. B(4,0) and D(8,10)
2. m=rise/run=5/4
y=mx+b
b=0
y=(5/4)x
point (16/20) , 20=5/4*16, 20=20 true , so point (16/20) is on the line
3.point(20,24) , y=(5/4)x, 24=(5/4)*20, 24=25 false, so point (20,24) is not on the line
4. point(80,100) , y=(5/4)x, 100=(5/4)*80, 100=100 true, so point (80, 100) is on the line
5. you need substitute values of x and y into equation y=(5/4)x, if it will be true, then the point is on the line
