Relationship of circles and polygons

[Ihatdogs10]

radius and a tangent

 

[Harry_the_cat]

I mean what is the measure of it (in degrees)?

 

[Ihatdogs10]

90 since it is a radius I mean XP

 

[Harry_the_cat]

Right and what other angle in your diagram is 90 degrees?

 

[Ihatdogs10]

QYOm?

 

[Ihatdogs10]

angle QYO?

 

[Harry_the_cat]

Do you mean YQO? the right angle is at Q, yes?

 

[Ihatdogs10]

okay yes angle Q is right angle

 

[Harry_the_cat]

Remember the letter in the middle of the three letters is at the vertex (pointy bit) of the angle

 

[Harry_the_cat]

OK, so ... have you learnt about similar triangles?

 

[Ihatdogs10]

similar triangles? no right and isosceles only

 

[Ihatdogs10]

wait is it sss and sas?

 

[Harry_the_cat]

Similar triangle have the same shape, but not the same size.

 

[Ihatdogs10]

okay so the given has similar triangle?

 

[Harry_the_cat]

wait is it sss and sas?

Yes that sort of thing!! AAA in this case. Do you remember what the A's stand for?

 

[Ihatdogs10]

ANGLE ANGLE ANGLE?

 

[Ihatdogs10]

PX·QO = QY· PO IS AAA?

 

[Harry_the_cat]

No, not there yet, but soon. Hang in there.

So, if the three angles in one triangle are the same as the three angles in another triangle, then the triangles are similar, Yes?

 

[Ihatdogs10]

yes

 

[Harry_the_cat]

Look closely at triangle POX and triangle QOY. We know that angle at P and at Q are the same (both 90). Can you give me two other angles which are the same?