triangle
octagon
9 diagonals
There are 275 diagonals in a shape with 25 sides. The formula is n*(n-3)/2
The diagonals of a rectangle do not cross at right angles
A nanogon has no diagonals because there is no such shape. A nonagon, on the other hand, has 9*(9-3)/2 = 27 diagonals.
I am sure that a shape with six side has 9 diagonals. (I found out cause I really wanted to help people.)
It has 27 diagonals
Any quadrilateral (4-sided shape) has 2 diagonals.
35 diagonals
No because a nonagon which is a 9 sided shape has 27 diagonals
9 diagonals
There are 54 diagonals in a 12 sided shape
There is none. A 5 sided shape is a pentagon but that has 10 diagonals, not 2.
A convex shape.
Only a chevron has diagonals intersecting outside the shape. The diagonals of a symmetric chevron will intersect at right angles.
A hexagon has 9 diagonals