In ΔABC, DE || BC in such a way that A-D-B and A-E-C. If m ∠ACB = 40°, then m ∠DAE + m ∠ADE = _____.
Answer & explanation
Correct answer: option 3

Here, we have a triangle ABC in which DE is parallel to BC
So, the \(\angle\)ACB = \(\angle\)AED = \({40}^\circ\)
Now, consider the triangle ADE as we know that
Sum of the angles of a triangle = 180
= \(\angle\)ADE + \(\angle\)DAE + \(\angle\)AED = 180
= \(\angle\)ADE + \(\angle\)DAE + 40 = 180
= \(\angle\)ADE + \(\angle\)DAE = \({140}^\circ\)
Therefore, the required angle is \({140}^\circ\).