Purchase Solution

Circumscribed circles

Not what you're looking for?

Ask Custom Question

The circumscribed circle is the circle passing through the three vertices of a triangle ABC. Assume the following results from geometry. The perpendicular bisectors of the sides of a triangle meet in a point O that is the center of the circumscribed circle.

a) According to a theorem from geometry, the measure of the angle AOC is twice that of angle B. What theorem is this? (State the theorem in complete sentences)

b) Draw a perpendicular from the center O to AC, meeting AC at T. Denoting the length of the side opposite to the angle B by b, explain why AT=TC-b/2.

c) Explain why triangle ATO is congruent to triangle CTO.

d) Use the results in parts (a) and (c) to show that angle COT = angle B.

e) Us the result in part (d) to show that the radius R of the circumscribed circle for triangle ABC is equal to b/(2 sin B). The use the law of sines to conclude from this that
R = ___a_____ = _____b______ = _____c_____
2 sin A 2 sin B 2 sin C

f) Let A denote the area of the triangle ABC. Show the radius R of the circumscribed circle is given by
R = __abc___
4A
hint: use the result from part (e)

Purchase this Solution

Solution Summary

This uses a circle circumscribed through the vertices of a triangle, and answers questions regarding congruency and angle measures.

Solution Preview

Please see the attachment.

The above graph is for this problem.
a. The theorem is: the angle at the center is twice of the angle of circumference for a given chord in a cicle.
b. In your problem, the side opposite to the angle is . So . Since is ...

Purchase this Solution


Free BrainMass Quizzes
Solving quadratic inequalities

This quiz test you on how well you are familiar with solving quadratic inequalities.

Know Your Linear Equations

Each question is a choice-summary multiple choice question that will present you with a linear equation and then make 4 statements about that equation. You must determine which of the 4 statements are true (if any) in regards to the equation.

Multiplying Complex Numbers

This is a short quiz to check your understanding of multiplication of complex numbers in rectangular form.

Geometry - Real Life Application Problems

Understanding of how geometry applies to in real-world contexts

Exponential Expressions

In this quiz, you will have a chance to practice basic terminology of exponential expressions and how to evaluate them.