Find the best answers to your questions with the help of IDNLearn.com's expert contributors. Ask anything and receive prompt, well-informed answers from our community of knowledgeable experts.
Sagot :
Answer:
A. x = 4
B. ∠C = 80°
Step-by-step explanation:
A.
The sum of interior angles in a pentagon is 540°. We can write an equation for the sum of angles using this fact. Clockwise from lower left, we have ...
140° +(20x)° +100° +(16x +16)° +(160 -5x)° = 540°
31x +416° = 540° . . . . . . collect terms
31x = 124° . . . . . . . . . . subtract 416°
x = 4
__
B.
The measure of angle C is found by substituting the value of x into the given expression for angle C.
(16x +16)° = (16(4) +16)° = 80°
Angle C is 80°.
_____
Additional comment
It can be useful to remember that the sum of interior angles of an n-gon is ...
(180°)(n -2)
This can be derived from the fact that the sum of exterior angles is always 360°.
These relations apply to convex polygons. YMMV when there are reflex angles or when sides cross each other.
Thank you for contributing to our discussion. Don't forget to check back for new answers. Keep asking, answering, and sharing useful information. Find clear answers at IDNLearn.com. Thanks for stopping by, and come back for more reliable solutions.