The sides AB and AC of △ABC are produced to points D and E, respectively. The bisectors of ∠CBD and ∠BCE meet at P. If ∠A=72
∘
, then the measure of ∠P is:
- A55
∘ - B65
∘ - C54
∘ - D35
∘
Solution & Step-by-step Explanation
The point P is the ex-center of △ABC formed by the exterior angle bisectors at vertices B and C.
The standard formula for the angle formed by exterior angle bisectors is:
∠P=90
∘
−
2
∠A
Given ∠A=72
∘
:
∠P=90
∘
−
2
72
∘
∠P=90
∘
−36
∘
=54
∘
The standard formula for the angle formed by exterior angle bisectors is:
∠P=90
∘
−
2
∠A
Given ∠A=72
∘
:
∠P=90
∘
−
2
72
∘
∠P=90
∘
−36
∘
=54
∘