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Work with Circles

Hi I really need help with the three questions. Please, let me know if the solutions I have done are correct or not. :smile:

Original post by strangepath

Hi I really need help with the three questions. Please, let me know if the solutions I have done are correct or not. :smile:

I can't really remember the circle theorems, but the last one is right and I'm pretty sure the first one is too. :smile:

though you haven't finished the last question . . .

(edited 11 years ago)

Reply 2

dudefrom93

Original post by joostan

I can't really remember the circle theorems, but the last two are right and I'm pretty sure the first one is too. :smile:

though you haven't finished the last question . . .

I am only half done with the questions and needed help with the rest of them. I would be really glad if someone helped me solve it. :redface:

Reply 3

TenOfThem

First one is not complete
Second one is wrong ... and your labelling is awful what is <D meant to be as there are 3 angles at D ... CDB=79 would be correct but of no use to you

The part of (3) that you have done is correct

(edited 11 years ago)

Reply 4

dudefrom93

Original post by TenOfThem

Could you help me complete it, please? I need to hand it in 2 hours. Please

Reply 5

TenOfThem

Original post by strangepath

Could you help me complete it, please? I need to hand it in 2 hours. Please

(1) is almost done you just have not answered the question ... I assume that you know the total degrees around a point

(2) Use a triangle to write down the value of ACB, then write down the value of ADB using one of the rules

(3) If you know CDB then you know CAB (same rule that you need to know in 2)

(edited 11 years ago)

Reply 6

Matt San

*Reflex angle is greater than 180

Agree with TenOfThem in that the lablelling is awful. I do, however, think the angle CDB=79 is relevant in finding ADB.

Reply 7

TenOfThem

Original post by Matt San

I do, however, think the angle CDB=79 is relevant in finding ADB.

You must be taking a different approach to my suggested one

Reply 8

dudefrom93

Original post by TenOfThem

You must be taking a different approach to my suggested one

For Q1 the answer is 290 deg and
for Q3 the answer is 40 def

am I correct?

i really don't know how I should find q2.

Reply 9

Matt San

TOT,

Oh yeah, see where you're coming from. I was using ABC (since this was already given) and CDB (as this was obtained already by thread starter).

cheers

Reply 10

Matt San

Original post by strangepath

For Q1 the answer is 290 deg and
for Q3 the answer is 40 def

am I correct?

i really don't know how I should find q2.

You can find ACB from properties of a triangle. Other than opposite angles being 180, what other properties are special to a cyclic quad? Or, the other circle theorum is Angles extended on the circumference from the same sector are "........."

Reply 11

TenOfThem

Original post by strangepath

For Q1 the answer is 290 deg and
for Q3 the answer is 40 def

am I correct?

i really don't know how I should find q2.

yes

have you done as I said

Reply 12

TenOfThem

Original post by Matt San

TOT,

Oh yeah, see where you're coming from. I was using ABC (since this was already given) and CDB (as this was obtained already by thread starter).

cheers