9x9+81
81/7= 81 over 7, or 11.6
I think the answer would be 4n
Answer:
Step-by-step explanation:
D is the answer
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:
-13
Step-by-step explanation: