Answer:
m∠CDE = 60°
Explanation:
Given that the arc at the center = 2 times the arc at the circumference, we have;
Angle at the center = arc CE = 120°
Whereby the angle at the circumference is given as m∠CDE and it is opposite the circle arc CE
We note that m∠CDE is the acute angle between chord DC and DE
Therefore, we have;
Angle at the center = 120° = 2 times the arc at the circumference = 2 × m∠CDE
120° = 2 × m∠CDE
m∠CDE = 120/2 = 60°
Therefore the angle of m∠CDE is equal to 60°.