In the given figure, BE ⊥ AC, ∠DAC = 30° and ∠DBE = 40°. Find ∠ACB and ∠ADB.
In triangle BEC we have,
B = 40O and
E = 90O
So,C = 180O – (90 + 40)
=50O
Therefore,ACB = 50O
Now intriangle ADC we have,
A = 30O and
C = 50O
So,D = 180O – (30 + 50)
=100O
Therefore,
ADB +
ADC = 180 (sum of angles on straight line)
ADB + 100 = 180
ADB = 180 – 100
= 80O