Since the triangle is equilateral, all its angles are equal to 60°
AO is the bisector⇒∠OAD = 30°
AO is the hypotenuse, ∠OAD = 30°⇒
OD=5*2=10m
By the Pythagorean theorem
Answer: A) 
m²
P.S. Hello from Russia and sorry for my bad english :^)
A regular polygon is drawn in a circle so that each vertex is on the circle
Each of the central angles has a measure of 40
360 / 40 = 9
so the polygon has 9 sides
Answer is the second option
9
Answer:
-2b/(a-b)
Step-by-step explanation:
1− (a+b/a−b)
We need to get a common denominator of a-b
1 = (a-b)/(a-b)
Replace 1 with (a-b)/(a-b)
(a-b)/(a-b) - (a+b)/(a-b)
Put over the common denominator
(a-b) - (a+b)
-----------------
(a-b)
Distribute the minus sign.
(a-b) - a-b)
-----------------
(a-b)
a-a-b-b
---------------
a-b
-2b
----------
a-b
345/8 is the another one yes
