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 = _________.
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 i.e. 140°.
Given that
In ΔABC, DE ∥ BC
If m∠ACB = 40°
Calculation
∠ ACB = ∠ AED = 40º (Corresponding angles)
In triangle ADE,
⇒ ∠ DAE + ∠ ADE + ∠ AED = 180º
⇒ ∠ DAE + ∠ ADE + 40º = 180º
⇒ ∠ DAE + ∠ ADE = 180º - 40º = 140º