Here's an interesting problem I posed to one of my classes (diagram to follow).

Question

anonymous · Answer

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Given that this is a square circumscribed about a circle. Find the radius of the circle.

sasogeek · Answer

what is the 6 and 12?

anonymous · Answer

The side of the square is 12?

anonymous · Answer

Are the sides of the rectangle drawn in the corner of the square that have one vertex that touches the circle.

anonymous · Answer

oh - 6 and 12 are the sides of the little rectangle :)

anonymous · Answer

If the 12 was the side of the square it'd make it too easy :P

anonymous · Answer

not if you are teaching a kindergarten class :)

sasogeek · Answer

i'll try to solve this on paper, take a pic and upload it, solving it here will take me all day

anonymous · Answer

is the radius 30 ?

anonymous · Answer

It is!

anonymous · Answer

I have it too

sasogeek · Answer

please tell me this is calculus cos i don't seem to figure out anything algebra in there :s

anonymous · Answer

it is not calculus, it is geometry :-)

anonymous · Answer

I posed it to my calculus class, but really it's only using geometry to solve.

sasogeek · Answer

meh, I hated geometry equations and formulas :( i guess its time i revisited it.

anonymous · Answer

making a drawing for urself helps a lot