Answer:
Step-by-step explanation:
Answer:
I think it's C but I might be
Step-by-step explanation:
I can't read that language but I'll guess it says write a second degree equation then solve for n when d=10.



Answer: n² - 3n - 20 = 0
That doesn't factor so there is no integer n solution.
That means there are no polygons with 10 diagonals.

Answer:
An isosceles triangle
Step-by-step explanation:
An isosceles triangle has 3 sides and has two equivalent sides with the same measure