Answer:
See below ~
Step-by-step explanation:
Q9
Q10
9. x = 200 and y = 100
10. x = 68 and y = 99
Question 9
The measure of an arc is the measure of its central angle.
⇒ x = 200
This is a non-cyclic quadrilateral as not all its vertices touch the circumference of the circle.
The angle at the center is twice the angle at the circumference.
⇒ y = 200 ÷ 2
⇒ y = 100
Question 10
This is a cyclic quadrilateral as all its vertices touch the circumference of the circle.
The opposite angles in a cyclic quadrilateral add up to 180°.
⇒ x + 112 = 180
⇒ x = 68
⇒ y + 81 = 180
⇒ y = 99
