Answer:
e
Step-by-step explanation:
THEOREM:
- Angle sum property —: The sum of interior angles of a triangle is 180°.
ANSWER:
Let the missing angle be x.
By angle sum property,
- ∠x + 20° + 80° = 180°
- ∠x + 100 = 180°
- ∠x = 180° – 100°
- ∠x = 80°
So, <u>Correct choice</u> - [C] 80°.
Each of the triangles are equal in base length, height, and area. Remember the formula for the area of a triangle. The area of any triangle is 1/2 times the length of the base (which, in the polygon, is the length of a side) multiplied by the height (which is the same as the apothem in regular polygon)
X = 180 - (90 + 47)
x = 180 - 137
x = 43
answer angle x = 43