circle theorem

[rotund coral]

What circle theorem do I use to answer this question

[sturdy crystal]

You can use the fact that OQS is isosceles

[rotund coral]

How do you know

[sturdy crystal]

OQ and OS are both radii

[rotund coral]

Oh yes

[rotund coral]

Do you have an idea on how to find z

[still raft]

that angle isn't 68 btw

[sturdy crystal]

Ye its another isosceles triangle

[rotund coral]

Which triangle

[sturdy crystal]

Did u understand part a

[rotund coral]

I got this one

if that’s what your asking

youre

[sturdy crystal]

No I mean part a for this

[rotund coral]

Ah no

I didn’t realise part b was to find z

how would you find y?

[sturdy crystal]

Part a uses the ||cyclic quadrilateral|| theorem

And also that OBC is isosceles

[rotund coral]

How is it not 68?

[rotund coral]

So y is 68?

Unless I got that wrong

[sturdy crystal]

Which other angle is also equal to y

[sturdy crystal]

No they want you to show its 35

[rotund coral]

Oh yh

Oh I see it’s not 68

[sturdy crystal]

Try find OCB

[rotund coral]

35

Because equal to 180

122+33+35

[sturdy crystal]

112 but yes

[rotund coral]

mistake

[sturdy crystal]

So now how would you find angle x

[rotund coral]

Z?

[sturdy crystal]

First x

[rotund coral]

Where’s x

X

[sturdy crystal]

BOC

[rotund coral]

I just put that as 2z

[sturdy crystal]

Oh right

[rotund coral]

Well =180

three angles

[sturdy crystal]

Yep

[rotund coral]

so just subtract 35x2

[sturdy crystal]

Ye then halve it

[rotund coral]

55

[sturdy crystal]

Yep