A trapezoid is a 4 sided polygon belonging to the class of 4 sided quadrilaterals
octagon
A decagon
There are 22
A triangle has three angles.
A polygon with 6 sides is an hexagon
Yes a square is a regular 4 sided polygon
360 degrees
any ellipse, any pie-wedge of a circle, etc.
No, not every trapezoid is an isosceles trapezoid.
A four sided polygon can be a square, a parallelogram, a rectangle, a rhombus or a kite.
An isosceles trapezoid
The altitude of a trapezoid bisects the bases of the trapezoid.