Question

How can I solve this question???

Answer 1

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)

$360\°/5=72\°$

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