Answer:
x = 140°
Explanation:
the secant- secant angle 10° is half the difference of the intercepted arcs
10° =
(30 - ? )° ( multiply both sides by 2 to clear the fraction )
20° = 30 - ? ( subtract 30° from both sides )
- 10 = - ? ( multiply both sides by - 1 )
10° = ?
the lower arc is a semicircle = 180°
the sum of the arcs in a circle = 360° , then
x = 360° - 180° - 30° - 10° = 360° - 220° = 140°