Answer:
144°
Step-by-step explanation:
step 1
Find the measure of the central angle of the regular pentagon
Divide 360 degrees by 5 (the number of sides)

Let
c----> the center of the pentagon
we know that
m∠ECA=72°
m∠ACB=72°
therefore
m∠ECB=m∠ECA+m∠ACB
substitute the values
m∠ECB=72°+72°=144°
The measure of angle ECB is equal to the degrees that the pentagon rotate
Answer:
20
Step-by-step explanation: -13 to 7 think about that. We have to add 13 to make it 0. Then we add 7. So 13 plus 7 is 20. Enjoy :)
Answer:
-1/8
Step-by-step explanation: