Question

If angle m acd = 100 and angle m b =60, find angle m a

Answer 1

m<ACD = 100
m<B = 60

so
m<ACB = 180 - m<ACD
m<ACB = 180 - 100
m<ACB = 80

m<A = 180 - (60 + 80)
m<A = 180 - 140
m<A = 40

Answer 2

The measure of ∠BAC is 40° .

Explanation:

As given the figure in the question be as follow .

∠ACD = 100° , ∠B = 60°

Noe by using the the exterior angle is equal to the sum of the interior angle .

Thus

∠ACD = ∠CBA + ∠BAC

Put all the values in the above

100° = 60° + ∠BAC

∠BAC = 100° - 60°

= 40°

Therefore the measure of ∠BAC is 40° .