Question

Lines CD and DE are tangent to circle A as shown below: Lines CD and DE are tangent to circle A and intersect at point D. Arc CE measures 125 degrees. Point B lies on circle A. If arc CE is 125°, what is the measure of ∠CDE? 55° 62.5° 117.5° 125°

Answer 1

@mathmale please help me

Answer 2

PLEASE HELP :)

Answer 3

do you know that a radius to circle and a tangent are always at right angles?

Answer 4

yes

Answer 5

So - you can add 2 right angles to the diagram

Answer 6

okay.

Answer 7

the line from the centre bisects the angle at the centre AND the angle CDE

Answer 8

yes... then what...

Answer 9

so - what is angle CAD?

When you know that - what is angle CDA?

Answer 10

90?

Answer 11

I think that was a guess.

I said above
"the line from the centre bisects the angle at the centre AND the angle CDE"

SO CAE = 125, what is CAD?

Answer 12

It wasn't I promise!! I honestly have no clue.

Answer 13

I'm sorry... I'm really struggling.

Answer 14

Just look at the diagram - I really have virtually told you the answer to this part:

I said above
"the line from the centre bisects the angle at the centre AND the angle CDE"
The angle at the centre is CAE = 125

It is bisected |(cut in half) by AD so
What is angle CAD?

Answer 15

62.5

Answer 16

OK good

Now look at the TRIANGLE ACD
Which angles do you know? (you know 2 of them..)

So what is the third one?

Answer 17

55

Answer 18

WAIT NO

Answer 19

wait ya 55

Answer 20

I asked for thtriangle ACD