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triangle ABC is isosceles with AB=AC and angle A=50°. the bisector of angle B and angle C meet at D. find the measure of BDC

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11 votes

Answer:

115 degrees

Explanation:

From what I'm visualizing, D is a point of another isosceles triangle within ABC, so to find the measure of angle BDC, we have to find the other angles first.

First, we have to find angle B and C. since this is an isosceles triangle and AB=AC, these two angles are equal and we find their angle measure by subtracting the known angle A, from the total measure of all angles in a triangle, 180

180 - 50 = 130

then divide that by two to get the two equal angles

130/2 - 65

angle bisector divides the angles in half so the measures of CBD and BCD are 65/2

that leaves the last remaining angle BDC. Again, we take the known angles and subtract them from 180

180 - 65/2 -65/2 = 115

User Uwe Mayer
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