Question

Find m∠BAC and m∠DAB in the figure shown below.

Answer 1

`\angle BAC=\angle DAE=80^(\circ)\\ \angle DAB=180-\angle BAC=180-80=100^(\circ)`

Answer 2

m∠BAC = 80° and m∠DAB = 100°

Explanation:

We are given, m∠DAE = 80°.

We have, ∠DAE and ∠BAC are vertical angles.

Since, 'Measure of vertical angles are equal'.

So, m∠BAC = m∠DAE = 80°.

Thus, m∠BAC = 80°.

Moreover, 'Sum of measures of angles in straight line is 180°'.

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°