Answer:
The measure, in degrees, of ∠ABC = 25°
Hence, option A is true.
Step-by-step explanation:
Given
The exterior angle m∠CBD = 155°
To determine
The measure of ∠ABC
We know that the exterior angle and interior angle are supplementary angles.
In other words, adding the interior angle and an exterior angle would give us 180°.
Here:
m∠CBD = 155° is exterior angle
∠ABC is the interior angle.
When we add m∠CBD and m∠ABC we would get 180°.
m∠CBD + ∠ABC = 180°
substituting m∠CBD = 155°
155° + ∠ABC = 180°
∠ABC = 180° - 155°
∠ABC = 25°
Therefore, the measure, in degrees, of ∠ABC = 25°
Hence, option A is true.
