Answer:
132°
Explanation:
An inscribed angle is half the measure of the arc it subtends. This means arc CB is twice the measure of inscribed angle CAB, so ...
arc CB = 2×∠CAB = 2×40° = 80°
Arc AC is twice the measure of inscribed angle ABC, so ...
arc AC = 2×∠ABC = 2×26° = 52°
The measure of central angle AOB is the same as the measure of arc AB.
x = ∠AOB = arcs AC +arc CB = 52° +80°
x = 132°