## Sunshine447 2 years ago Can someone please help me with this? The lesson explains it, but I just don't get it..... Jerry inscribed a quadrilateral ABCD in a circle, as shown below. http://learn.flvs.net/webdav/assessment_images/educator_geometry_v14/pool_Geom_3641_0800_Subtest_01_06/image0024e67730b.jpg If the measure of arc BCD is 250°, what is the measure of angle BCD?

1. Sunshine447

@amistre64 @phi

2. amistre64

3. Sunshine447

It's from the lesson...

4. amistre64

|dw:1354227203795:dw|

5. amistre64

notice that the angle at c ison the edge of the circle; there is a property that says this angle is half the arc across from it

6. Sunshine447

where does the 250 come from?

7. amistre64

BCD = 250 is stated in the question ....

8. Sunshine447

9. Sunshine447

okay

10. amistre64

i got no idea what its spose to be called :)

11. Sunshine447

okay haha

12. Sunshine447

I got 10 and 5 when I solved the part you wrote....... @amistre64

13. amistre64

360-250 is the arc that angle BCD is facing soo; BCD = (360-250)/2 = 110/2 = 55 to me

14. Sunshine447

ohhhhhhhhhhhhhhhhhhhh okay, so it's 55 because it's half of the opposite arc?