Question

The figure below shows a triangle with vertices A and B on a circle and vertex C outside it. Side AC is tangent to the circle. Side BC is a secant intersecting the circle at point X.

What is the measure of angle ACB?

Answer 1

Know the relationships between secant lines and assorted angles? The word half shows up in a lot of them....

Answer 2

I have no idea how to do this can you walk me through please..kinda need an answer fast...

Answer 3

All the formulas you need are right here:
http://www.regentsprep.org/Regents/math/geometry/GP15/CircleAngles.htm

Saying you want something fast makes this sound like a timed test. Read the CoC? http://openstudy.com/code-of-conduct and Terms http://openstudy.com/terms-and-conditions ? Specifically the part about the Anti-Cheating Policy.

Answer 4

No I just need to learn how to do this problem fast I was just asking for a walk through

Answer 5

I have like 15 more like it

Answer 6

and I think if Im just shown once I can do the rest by myself

Answer 7

You are given one arc segment of a circle. With the rules on that page, you can find out what the other arc segments are. From the arc segments you can find angle C. Then you have 2 angles of the triangle and could even solve the third.... but it onlt asks for C.

Answer 8

Start with 2. Inscribed Angle:

Answer 9

That gets you arc XA

Answer 10

Then use "a Tangent and a Secant:" with arc BA and arc XA and you will get ACB.

Answer 11

OKay thank you (:

Answer 12

I am sure the other 14 are different from the first, but the basic principal is the same: Look at what you are given, asked for, and missing. Then use what is given to find either what you are asked for OR find what is missing so what is missing can be used to find what is asked for.