Re: IF BC=45 find the measure of angle ABD
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07 Apr 2024, 03:33
D.
This problem tests your understanding of the relationship between a circle and an inscribed triangle.AABC is a right triangle. You are also given the chord length BC = 45°. From this you know that the inscribed angle BAC = 22.5°. The diagram shows angle ABC = 90° so you can find angle ACB with:
angle ACB = 180° - angle ABC - angle BAC = 180° - 90° - 22.5°= 67.5°
Next, the diagram shows chord BD is perpendicular to AC so you can use the properties of similar right triangles to show that angle ABD = angle ACB = 67.5°.
The correct answer is D.