Changes

,  06:49, 15 February 2014
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*Question Corner

*Question Corner
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= Hints for difficult problems =
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[[:File:polygon problem.odt]]= Hints for difficult problems =
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CLASS IX TOPIC POLYGONS
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ADDITIONAL PROBLEMS (problem no 3 )
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A polygon has 'n' sides .Two of it's angles are right angles and each of remaining angle isFind the value of 'n'.
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Step 1;(Students must understand the problem)
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In a polygon of side 'n' two angles are and other angles are each.We must find out              value of 'n'.
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Step 2(Students know the formula for sum of angles of polygon of side 'n')
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(2n-4)right angles.
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Step 3(Sum of the angles is equal to what?)
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There are 'n' angles in a polygon of side 'n'.Out of 'n' angles 2 angles are right anles and other (n-2) angles are each.
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(2n-4)  [itex]90^0[/itex]              = (n-2)[itex]\144^0+{2}{90}^0[/itex]Students know how to open the bracket and substitute the values)
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2n x - 4 x =
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=  (Brings similar terms at one side of the equation)
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=                  (Add and substract and simplify)
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=
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n          =                              (Devide and simplify)
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n        =      7

= Project Ideas =

= Project Ideas =