Question

Given: t is tangent at B.
AB is diameter.
https://media.glynlyon.com/g_geo_2012/7/groupi91.gif
If m DPB = 60°, then m DB = ? 30?
If m AF = 110°, then m DB = ? 70?
If AC=CD=DB, then m CPD = ? 60?

Answer 1

30, 70, 60. Are my answers correct?

Answer 2

Look at this again. If m DPB = 60°, then m DB = ? 30?

Angle DPB is a central angle and arc DB is the arc it cuts off. Is the measure of a central angle of a circle equal to 1/2 the measure of its intercepted arc?

Answer 3

hm =/

Answer 4

i just thought that it would be half of 60 so i assumed 30?

Answer 5

The good thing about Geometry is that we don't have to assume stuff because we have the theorems and postulates and definitions.

So, look in your book for how to find the measure of a central angle of a circle. The 30 is not correct.

Answer 6

would it be 120?

Answer 7

The arc of a central angle is NOT twice the arc.

Answer 8

or does it just stay a 60 without adding 60 more?

Answer 9

so 60 lol

Answer 10

If I may ask, why is it that you don't look up central angles in your text?

Answer 11

I did, i misread the whole paragraph

Answer 12

also because im very dull when it comes to math. i have a harder time understanding

Answer 13

Okay, so the measure of a central angle of a circle is the same as the measure of its intercepted arc.

Answer 14

And, now for some good news. My answers agree with yours on parts two and three although I now fear you guessed by looking. :)

Answer 15

I'm joining this late but I figured I'd redraw the graphic.

Answer 16

Acutely i did try haha

Answer 17

thats more helpfull