Prove question

**crossfire** · November 9th 2012, 05:45 PM

The radius of circle ABC, centre B is r1.
The radius of circle CDE, centre D is r2.

For the diagram above PROVE that AC/CE = r1/r2

:l

**crossfire** · November 9th 2012, 05:45 PM

This is a picture

**richard1234** · November 9th 2012, 06:23 PM

Hint: There are some similar triangles in the diagram...

**jakncoke** · November 9th 2012, 06:32 PM

How about this pic attached. $\frac{\sqrt(2)*r1}{\sqrt(2)*r2} = \frac{r1}{r2}$

**crossfire** · November 9th 2012, 06:43 PM

Jakncoke, I dont quite understand where and how you got those figures could you please explain?

**richard1234** · November 9th 2012, 07:11 PM

@jakncoke, that's only a specific case (for right isosceles triangles). It does generalize, using similarity.

**jakncoke** · November 9th 2012, 08:57 PM

yea my bad, i wasn't thinking.

Thread: Prove question