Answer:
The diagrams below explain the process with angles.
Step-by-step explanation:
In figure 1, a rectangle is drawn in the circle.
Since the acute angle being drawn by the hypotenuse is 40 degree in figure 2, thus we can say the other angle will be 50 degrees.
In figure 3, the rectangle is cut across its diagonal to form a kite shaped entity within the circle.
Now we know that m∠BDE = 40° = m∠ADB.
Also, m∠A = m∠E = 90°
Thus, m∠EBD = m∠ABD = 50° ⇒ m∠B = 100°
Also, m∠ADE = 80° ANSWER
