Given:
AB is the diameter of a circle.
m∠CAB = 26°
To find:
The measure of m∠CBA.
Solution:
Angle formed in the diameter of a circle is always 90°.
⇒ m∠ACB = 90°
In triangle ACB,
Sum of the angles in the triangle = 180°
m∠CAB + m∠ACB + m∠CBA = 180°
26° + 90° + m∠CBA = 180°
116° + m∠CBA = 180°
Subtract 116° from both sides.
116° + m∠CBA - 116° = 180° - 116°
m∠CBA = 64°
The measure of m∠CBA is 64°.
