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PRACTICAL GEOMETRY

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CLASS:7

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PREPARED BY

S.S.YADAV

TGT MATHS, JNV AMBEDKAR NAGAR

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CONSTRUCTION OF TRIANGLE

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  • WE LEARN HERE TO CONSTRUCT ANY

TRIANGLE GEOMETRICALLY.

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  • A triangle is a simple closed curve made of three line segments.

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  • It has three sides.
  • It has three angles.
  • It has three vertices.

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Construct a ΔABC in which ��AB=4.2cm, BC=5.5cm and ��CA=6.4cm.

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ROUGH FIGURE

  • Before starting the construction draw rough figure of the Δ ABC. Also write the measurements given in question.

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ACTUAL CONSTRUCTION

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STEPS OF CONSTRUCTION

1. Draw BC=5.5 cm.

2. Taking B as centre draw an arc of length 4.2 cm.

3. Taking C as centre draw an arc of length 6.4 cm

which intersect the previous arc at point A.

4.Join AB and AC.

Δ ABC is the required triangle.

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Some other key points to remember

  • A triangle cannot have two right angles.
  • A triangle cannot have two obtuse angles.
  • A triangle cannot have all three angles greater than 600 .
  • A triangle cannot have all three angles less than 600 .
  • Hypotenuse is the longest side in a right triangle.

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THANK YOU�……………….�………………�…………….� �KEEP GRASPING !