The measure of xy is 124 what is the measure of the tangent-chord angle xyz ?

Question

anonymous · Answer

attachment

anonymous · Answer

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anonymous · Answer

I got 236 by taking 124 away from 360

anonymous · Answer

Would angle Y and X be 59 ?

anonymous · Answer

Would 59 + 90 = XYZ ?

amistre64 · Answer

its the average of the subtended angles on both sides of the angle ...

amistre64 · Answer

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x = (a+b)/2

in this case b=0

anonymous · Answer

Oh ! 64 correct ?

amistre64 · Answer

almost :)  124/2 = 62

anonymous · Answer

That's what i meant lol -__ -

anonymous · Answer

Is there other methods to finding tangent-chords ?

amistre64 · Answer

you only need to know one method (a+b)/2 ... but it comes in a few varieties, ill draw them

anonymous · Answer

Okay thank you so much for taking your time to help (:

amistre64 · Answer

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amistre64 · Answer

this ones cool, think of the arc behind it as a negative .....

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amistre64 · Answer

in that last one:   (a+(-b))/2

anonymous · Answer

Are first and second (a+b)/2  ?

amistre64 · Answer

they all are,  consider the front arc as "a",  and the behind arc as "b"

when you are inside of the circle, your front and back will have defined values

when you are on the edge of the circle, your behind arc = 0

when you are completely outside of the circle, your behind arc is a negative

amistre64 · Answer

its just easier to remember this than .. how many different "thrms"?

anonymous · Answer

Yes it is, i think there was another one but i got confused and took it out of my notes

anonymous · Answer

How do you get the negative arc ?

amistre64 · Answer

its more of a visual :)|dw:1370551682946:dw|