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The rectangle in the corner is 2cm * 4 cm. Find radius of the circle. :)
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The rectangle in the corner is 2cm * 4 cm. Find radius of the circle. :)
Circle: x2 + y2 = r2
The rectangle point touching the circle has coordinates
-(r - 4), (r - 2)
Substituting:
(r - 4)2 + (r - 2)2 = r2
and this leads to
r2 - 12r + 20 = 0
which has the roots 2 qnd 10. Obviously 10 is the correct answer.
On the right track, but not quite there ;)
Whaaaaaaat??????Quote:
Originally posted by mendhak
... but not quite there ;)
I can't wait to see, why 10 should not be the correct answer!
You did ask for radius, right!
:embarassed:
Oh damn...
I was performing the calculations using 4cm * 8 cm :very embarassed:
OK, OK... the answer is 10.
What that means is you should pay more attention to the derivation itself than to the final numbers. Question: were you smoking at the time you figured that out? ;)
Why, yes. Yes I was. :D
I'll pay more attention next time. I'll be back with a tougher puzzle. Hopefully, you won't be able to solve it and will come crawling to me, BEGGING for a hint. :)
I'm all agog waiting for the next one to come. My face is looking like in the old days when I was broke, used to smoke and ran out of cigarettes.Quote:
Originally posted by mendhak
Why, yes. Yes I was. :D
I'll pay more attention next time. I'll be back with a tougher puzzle. Hopefully, you won't be able to solve it and will come crawling to me, BEGGING for a hint. :)
it was obvious.... did it in like 14 seconds,
there are 5 rectangles of length 4 cm in the big square, thus, 4 * 5 would be 20cm, the square has an area of 400cm^2,
so, 20/2 would give you the radius, which is 10cm.
14 seconds, after 15 days cool!
What if it was not to scale?Quote:
Originally posted by prog_tom
it was obvious.... did it in like 14 seconds,
there are 5 rectangles of length 4 cm in the big square, thus, 4 * 5 would be 20cm, the square has an area of 400cm^2,
so, 20/2 would give you the radius, which is 10cm.
then there would be no correct way of finding the Correct radius.
This would still give the correct answer.Quote:
Originally posted by krtxmrtz
Circle: x2 + y2 = r2
The rectangle point touching the circle has coordinates
-(r - 4), (r - 2)
Substituting:
(r - 4)2 + (r - 2)2 = r2
and this leads to
r2 - 12r + 20 = 0
which has the roots 2 qnd 10. Obviously 10 is the correct answer.
well that's because it's scaled,
it's just that it supposes the radius is r.
I think it's a sound assumption... If the radius is not r, then call it any name you like...Quote:
Originally posted by prog_tom
well that's because it's scaled,
it's just that it supposes the radius is r.
Honestly I don't understand what you mean.