Divide the nonagon radially into 9 congruent, equilateral isosceles triangle. Each triangle has vertex angle of 360°/9 = 40°.
Interior angle of polygon = 180°-40° = 140°.
Sum of interior angles = 9(140°) = 1260°
Answer:
The answer should be: r ≈ 8.21
Answer:
opposite sides have same slope
It would be A, Side Angle Side (SAS). Because you are given we congruent sides, and tow right angles. Using the reasoning of "If two two angles are both right angles then they are congruent" you can prove the angles congruent.
The reason it is not HL is because HL is used when it is given a right angle and the hypotenuse and one of the legs congruent. Therefore the only choice is Side Angle Side (SAS).
