Answer:
m∠BAC = 80° and m∠DAB = 100°
Step-by-step explanation:
We are given, m∠DAE = 80°.
We have, ∠DAE and ∠BAC are vertical angles.
<em>Since, 'Measure of vertical angles are equal'.</em>
So, m∠BAC = m∠DAE = 80°.
Thus, m∠BAC = 80°.
<em>Moreover, 'Sum of measures of angles in straight line is 180°'.</em>
So, m∠DAB + m∠BAC = 180°
i.e. m∠DAB = 180° - m∠BAC
i.e. m∠DAB = 180° - 80°
i.e. m∠DAB = 100°
Thus, m∠DAB = 100°