Hey Brilliants! I found this question in my book. Q-CD is a direct common tangent to two circles intersecting each other at A and B. Then angle CAD + angle CBD is equal to what?
The answer is 180°, Now what I wanna know is how the answer came 180°.

@Reynan Henry
–
Oh! OK! Thanks Reynan! You cleared my big doubt. Sorry last question. I dont know much about theories so please tell about what is alternate segment theorem?

@Dhaman Trivedi
–
Take a look
https://lh4.googleusercontent.com/proxy/EtyNHxDLxZTJK07Ycu6ZHDiCeLxmFMwHE3kovJnNo1217WVMbaghfOKmQUaiwbYYc7kOwWPK6Wp-Y72DhT9AMMmlrtTPiNfKfme-U0AsmB6_BPXiGICzPabmPVrA=w266-h189-nc

@Calvin Lin
–
Sir Calvin actually I do have the solution of this question, but there are some things where I just ask "Why it is happening" If you say I post my solution of book here and then you explain my Whys. Thanks

$</code> ... <code>$</code>...<code>."> Easy Math Editor

`*italics*`

or`_italics_`

italics`**bold**`

or`__bold__`

boldNote: you must add a full line of space before and after lists for them to show up correctlyparagraph 1

paragraph 2

`[example link](https://brilliant.org)`

`> This is a quote`

Remember to wrap math in $</span> ... <span>$ or $</span> ... <span>$ to ensure proper formatting.`2 \times 3`

`2^{34}`

`a_{i-1}`

`\frac{2}{3}`

`\sqrt{2}`

`\sum_{i=1}^3`

`\sin \theta`

`\boxed{123}`

## Comments

Sort by:

TopNewestIts easy right asume ab intersect cd at x then bax equal to bcx

Log in to reply

I don't got it can you explain in brief?

Log in to reply

Sorry i cant use the latex hehe. But angle bca is equal to angle bcx (alternate segment theorem) so bca + bcx = 90 analog bad + bdx = 90. Add them all

Log in to reply

Log in to reply

https://lh4.googleusercontent.com/proxy/EtyNHxDLxZTJK07Ycu6ZHDiCeLxmFMwHE3kovJnN

o1217WVMbaghfOKmQUaiwbYYc7kOwWPK6Wp-Y72DhT9AMMmlrtTPiNfKfme-U0AsmB6_BPXiGICzPabmPVrA=w266-h189-ncLog in to reply

Log in to reply

Log in to reply

Log in to reply

Also, I doubt that BCA + BCX = 90, because that is equal to ACX, which is ACD, which is not 90.

You are on the right track, but you just need to ensure that what you write is what you are thinking.

Log in to reply

Log in to reply

Good Question Brother, let me try this one!

Log in to reply

Swapnil Das I have given the solution given in book. Just tell me they Whys answer

Log in to reply

Ya, I just have to prove that the answer is 180.

Log in to reply

Log in to reply

Log in to reply

Log in to reply

I happened to see this note and one question came to my mind after observing the figure: Are the two circles congruent?

Log in to reply

That's the problem what I wrote in question, That's all. I also thought the same but no....No where proved that those are congurent

Log in to reply

Even if the circles arent congruent. The sum is still 180

Log in to reply

Do u know that cbda is a kite?

Log in to reply

Can you explain why it is a kite? Are you assuming that the circles are congruent?

Log in to reply

I have the same question as Calvin Sir

Log in to reply