If each exterior angle of a regular polygon is 45 degree. How many side does it have. Also name the

Geometry is mostly imagination. You must study the shapes until you can imagine one and inspect its parts mentally.

An exterior angle is measured by placing a straight edge along one side and rotating it to lie along the next side. If you have a square, that angle will be 90 degrees. An octagon has 45 degrees for the exterior angle. The sum of exterior angles around any polygon, regular or irregular, is 360 degrees, so for a regular polygon the angle is 360 divided by the number of sides. A hexagon has 6 sides, so the angle is 360/6 = 60 degrees. And so on.