Four.
A quadrliateral (or quadrangle).
Number of vertices in the plane figure = 4.
There need not be any. If there is one (or more) it can by at any of vertex (or vertices).
It must have lines which meet at the four vertices, but they cannot cross.
Quadrilaterals contain four line segments as well as four vertices where the lines meet. The four-sided object is also commonly referred to as a quadrangle.
A QUADRANGLE HAS 4 SIDES QUADRANGLE- QUAD MEANS 4
The sum of the angles in a quadrangle is 360 degrees.
9
4
10
o
three