Veins have valve but arteries do not. Explain this statement with reasoning.

Blood flows under low pressure in veins. So, there is chance of back flow of blood. To prevent this backflowof blood veins have valve. As blood flows under high pressure inside the arteries, there is no risk of backflow. Thats why arteries do not have valves. 

Usually arteries do not have valves. But two arteries originating from right and left ventricles have valves to prevent backflow of blood. These two valves ( aortic and pulmonary) are usually regarded as heart valves. But anatomically they are inside arteries.Most veins contain valves (known as the valvula venosa in the TA) to prevent backflow, i.e. ensuring that blood flow is always towards the heart ¹. Recent evidence shows that veins that were previously thought to be valveless, are now known to have valves, including the facial and superior ophthalmic veins.

The deep veins play a significant role in propelling blood toward the heart. The one-way valves in deep veins prevent blood from flowing backward, and the muscles surrounding the deep veins compress them, helping force the blood toward the heart, just as squeezing a toothpaste tube ejects toothpaste.