Answer:
C, B
Explanation:
The interior angle of a regular polygon is:
θ = (n - 2) × 180° / n
So a pentagon with 5 sides has an interior angle of:
θ = (5 - 2) × 180° / 5
θ = 108°
If we draw a line from the bottom left corner to the center, we get a right triangle. Using tangent, we can say:
tan (108°/2) = a / (7.6/2)
tan (54°) = a / 3.8
a = 3.8 tan (54°)
a = 5.2
Answer C
If the interior angle is 144, then the number of sides is:
144 = (n - 2) × 180 / n
144n = 180n - 360
360 = 36n
n = 10
Answer B.