Geometry - Circles and Squares.

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by Blimey72 » Tue Apr 12, 2011 2:06 pm
What I find curious is that none of the preparation materials I've seen really mention what we have to assume and not assume.

My Manhattan Geometry book says nothing about this, nor does the Knewton course I'm taking.

And GMAC too don't make it explicit, creating the confusion in the first place!

As you you said, Idoolik, just the instructions are like CR problem. Very frustrating for a multiple-choice exam, especially when we know what's at stake here.
Last edited by Blimey72 on Tue Apr 12, 2011 2:14 pm, edited 1 time in total.

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by ldoolitt » Tue Apr 12, 2011 2:12 pm
I think that the combination of Brent's video and the above discussion about points on a line covers most or all of the assumptions that I have ever had to use. I don't think I've ever gotten a practice problem wrong because I did or didn't assume something that wasn't or was true, respectively.

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by srcc25anu » Tue Apr 12, 2011 11:14 pm
Can someone explain how can we do this using Statement 2 alone?

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by Blimey72 » Wed Apr 13, 2011 1:47 am
Hi srcc25anu,

From the question stem, we know that the rectangle is 2r high and 3r wide (r being the radius of the identical circles). So the area of the rectangle (in terms of r) is 2r x 3r, or 6r^2.

From statement 2, 6r^2 = 294. As the sides can't be negative, this is sufficient to solve for r and, in turn, for the rhombus in the middle.