Answer:
z = 110°
Step-by-step explanation:
Angles z and the one marked 70° form an linear pair, hence are supplementary.
z = 180° -70° = 110°
<h3>Angles where chords cross</h3>
The angle made by two chords is half the sum of the arcs intercepted by those chords. Here, that means ...
70° = 1/2(60° +x) ⇒ x = 140° -60° = 80°
The arc w completes the circle of 360°, so we have ...
w +x +79° +60° = 360° ⇒ w = 360° -219° = 141°
Finally, z is the average of w and 79°:
z = (w +79°)/2 = (141° +79°)/2 = 110° . . . as above
