In triangle ABC,
\(\angle ABC + \angle ACB + \angle BAC = 180\)
\(b + c + \angle BAC = 180\)
\(\angle BAC = 180 - (b + c)\)
DC is a straight line,
so \(\angle DAB + \angle BAC = 180\)
\(a + 180 -(b+c) = 180\)
\(a = b+c\)
This is also known as the
exterior angle theorem. OA,CCarcass wrote:
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In the figure above, what is a in terms of b and c ?
A. 180 – b + c
B. 180 + b + c
C. b + c
D. b + c − 180
E. b + c + 180
Kudos for the right answer and explanation
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