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| Create a new page and type <nowiki>{{subst:Math-Content}}</nowiki> to use this template | | Create a new page and type <nowiki>{{subst:Math-Content}}</nowiki> to use this template |
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− | = TRIANGLES =
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− | Mark three
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− | non-collinear point P, Q and R on a paper. Join these pints in
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− | allpossible ways. The segments are PQ, QR and RP. A simple close
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− | curve formed by these three segments is called a triangle. It is
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− | named in one of the following ways.
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− | Triangle PQR or
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− | Triangle PRQ or Triangle QRP or Triangle RPQ or Triangle RQP .
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− | [[Image:KOER%20Triangles_html_m55b3a2cf.png|picture of equilateral triangle]] PQR
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− | A triangle is one of the basic shapes of geometry:
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− | a polygon with three corners or vertices and three sides or edges
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− | which are line segments.
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− | In fact, it is the
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− | polygon with the least number of sides.
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− | A triangle PQR
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− | consists of all the points on the line segment PQ,QR and RP.
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− | The three line segments, PQ, QR and RP that form
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− | the triangle PQ, are called the sides of the triangle PQR.
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− | '''Angles: '''
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− | A triangle has three angles. In figure, the three
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− | angles are ∠PQR ∠QRP and ∠RPQ
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− | '''Parts of triangle:'''
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− | A triangle has six parts, namely, three sides,PQ
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− | QRand RP.Three angles ∠PQR ∠QRP and ∠RPQ. These are also known
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− | as the elements of a triangle.
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− | '''Vertices of a Triangle '''
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− | The point of
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− | intersection of the sides of a triangle is known as its vertex. In
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− | figure, the three vertices are P, Q and R. In a triangle, an angle is
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− | formed at thevertex. Since it has three vertices, so three angles are
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− | formed. The word triangle =tri + angle ‘tri’ means three. So,
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− | triangle means closed figure of straight lines having three angles.
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− | == Evaluation ==
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− | == Self-Evaluation ==
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| == Further Explorations == | | == Further Explorations == |