Polygon

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Polygon

by whatjrohwants » Sun Feb 19, 2012 9:34 pm
each bottom side is 90 degrees. what is the area of the polygon?
OA is 0.3
but I have no I idea how to get to that answer.
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Last edited by whatjrohwants on Mon Feb 20, 2012 4:46 pm, edited 1 time in total.
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by LalaB » Sun Feb 19, 2012 11:19 pm
I didnt get the same answer 0.3

my approach -

to find the area of polygon u should subtract the area of a square from the area of a triangle

S of square=4*4

S of a triangle =1/2*4*h

h=sqroot of ((sqroot13)^2-2^2)=3

4*4-1/2*4*3=16-6=10
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by whatjrohwants » Mon Feb 20, 2012 8:11 am
Hey lalaB thanks for your answer. However, the question doesn't say it's a square.

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by Anurag@Gurome » Mon Feb 20, 2012 8:20 pm
whatjrohwants wrote:Hey lalaB thanks for your answer. However, the question doesn't say it's a square.
If you look at the figure, the length and width is given as 4, and when both the length and width are the same then it is square. Hope this answers your query.
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by whatjrohwants » Mon Feb 20, 2012 8:28 pm
But the length of the left side is not given. Only info given is four sides(4,4, and two sqr13) and two angles (two 90s)...

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by theloniousdave » Wed Feb 22, 2012 7:10 am
I don't think your answer is correct. .3.

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by whatjrohwants » Wed Feb 22, 2012 7:36 am
sorry i just checked the answer..it's actually 10..
So I guess it's right to assume that it's a square.

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by optimist.tageja » Wed Feb 22, 2012 8:25 am
we do not have to 'assume' that its a square, the figure itself says its a square,
-- The bottom two angles are 90 degrees (so either it is a square or a rectangle)
-- The length and the width of the given figure are 4 and 4 (with bottom angles 90 degrees it is clear that the given figure is a square)
whatjrohwants wrote:sorry i just checked the answer..it's actually 10..
So I guess it's right to assume that it's a square.

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by whatjrohwants » Wed Feb 22, 2012 8:41 am
I have to disagree on that optimist.tageja. Without knowing either angle of the top corners you cannot say it's a definite square. Think of a trapezoid with two bottom right angles and same bottom and one side lengths.

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by [email protected] » Wed Feb 22, 2012 4:14 pm
In the GMAT exam, all figures are drawn to scale, unless specified otherwise, hence if a figure looks like a sqaure more than 99% of the time, it is a square.