5 Shapes, 8 sides
2 shapes
It can form two quadrangles and three triangles. It has seven sides.
2 faces can't share the same face, and they cannot share ALL vertices and edges either
There are different formulae for different shapes. And since you have not bothered to share any information about the shape, I cannot provide a more useful answer.
The shapes would be around 9 and 8 sides in total.
2 shapes
It can form two quadrangles and three triangles. It has seven sides.
2 faces can't share the same face, and they cannot share ALL vertices and edges either
A 3-sided polygon is a triangle. There is no diagonal for that shape since all non-adjacent vertices share a line segment!
There are different formulae for different shapes. And since you have not bothered to share any information about the shape, I cannot provide a more useful answer.
The flag of Nepal is the only national flag that is not rectangular in shape. It consists of two stacked triangular shapes.
they are fluid
The shapes would be around 9 and 8 sides in total.
The trick to making shapes with a certain number of lines is to allow the shapes to share lines between each other. You also have to make sure that you aren't letting them share too many lines; in fact, to get thirteen lines for squares, you'll need to share three lines (technically called segments in mathematics). One way to do this is to simply draw a rectangle and sketch three lines between it.
If they share a part or whole of a side and provided they do not overlap, then depending on the shape of the triangles, the result can be a triangle, quadrilateral or a concave pentagon. Otherwise you can get other shapes such as a 6-pointed star.
The 12 pentagons each have 5 vertices, none share vertices with any other pentagon. Every hexagon vertex is a shared one with a pentagon, so ignore them to avoid repeats. 12 * 5 = 60 vertices.
North America and South America have some similarities in shape, with both having a tapering point at the southern end. Africa and South America also share some similarities in their western coastline shapes.