In the figure, if AB∥DE, ∠BAC=35° and ∠CDE=53°, find ∠DCE.
Solution:
Given, AB∥DE, ∠BAC=35°, ∠CDE=53° According to the question, ∠BAC=∠CED (Alternate interior angles) ∴∠CED=35° Now, ∠DCE+∠CED+∠CDE=180° (Sum of the interior angles of the triangle) ⇒∠DCE+35°+53°=180° ⇒∠DCE+88°=180° ⇒∠DCE=92°