Answer:
40
Step-by-step explanation:
∠BAC and ∠CAD are supplementary angles as they are formed on a line of the triangle.
Supplementary angles add up to 180°
This means ∠BAC + ∠CAD = 180
We are given that ∠CAD = 140
So ∠BAC + 140 = 180
==> subtract 140 from both sides
∠BAC = 40°
