Answer:
∠ ABD = 40°
Step-by-step explanation:
See the diagram attached to this answer.
Points A, B, and C are on line AC.
Since ABC is a straight line so, the AC line forms 180° at point B.
Now, a line extends from point B up and to the left to point D.
Given that, angle CBD has a measure of 140° i.e. ∠ CBD = 140°.
Now, ∠ ABD and ∠ CBD are supplementary i.e. ∠ ABD + ∠ CBD = 180° {Since ABC is a straight line}
Hence, ∠ ABD = 180° - ∠ CBD = 180° - 140° = 40° (Answer)
