Standard - 9

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Dear children, We have travelled much In the world of math Let’s continue Our explorations Our findings We have much more to go ahead In Mathematics To the ever widening world of Numbers To the precise reasoning of Geometry Let’s continue our search…. To the higher levels to Algebra

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Contents

Chapter 1 : similar triangle 1.Angles and sides 2.Sides and angles 3.The third way

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CHAPTER :1 SIMILAR TRIANGLE If all sides of one triangle are equal to the sides of another triangle, then the angles of the triangles are also equal.

Since sides are equal, angles must also be equal,

That is, each angle of AABC is equal to some angle of APOR. But how do the angles match? Which angle is equal to