Ncert Solutions For Class 8 Maths Ex 4.2

Ncert Solutions For Class 8 Maths Chapter 4 Ex 4.2

Question 1: Construct the geometry of the following quadrilaterals by the given data.

i) Quadrilateral of the word called GIFT

  GI= 4 cm

IF= 3 cm

TG= 2.5 cm

GF= 4.5 cm

IT= 4 cm

ii) Quadrilateral BOLD

OL =7.5 cm

 BL=6 cm

BD=6cm

LD =5 cm

 OD=10 cm

iii) Rhombus MEND

MN=5.6 cm

 DE=6.5 cm

 

Answer:

The rough text of the quadrilateral can be drawn here:

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ΔGITcan be constructed by following measurements

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2) Vertex F is 4.5 cm away from vertex L and 5 cm away from vertex I. Therefore, while taking L and I as centres, draw arcs of 4.5 cm radius and 3 cm radius respectively, which will be intersecting each other at point F.

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3) Join F to T and F to I.

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BEAT is the required to form the quadrilateral.

 

ii) A rough sketch of this the diagram quadrilateral can be as follows.

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1) ΔGDLcan be constructed by following measurements of the quadrilateral

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2) Vertex O is 10 cm to the vertex D and 7.5 Cm from vertex L. Therefore, while taking D and L as centres, draw arcs of 10 cm radius and 7.5 cm radius respectively. These will intersect each other at point O.

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3) Join O to L and B.

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4) BOLD is the required quadrilateral.

 

iii) We know that the diagonals of a rhombus always bisect each other at 90.Let us assume that these are intersecting each other at a point O in this rhombus.

Hence EO=OD=3.25

A rough sketch of the rhombus can be drawn as follows:

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1) Draw a line segment MN of 5.6 cm and also draw its perpendicular bisector. Let it intersect the line segment MN at point O.

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2) Taking O as centre, draw arcs of 3.25 cm radius to intersect the perpendicular.

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3) Join points D and E to the points B and N.

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MEND is the required quadrilateral.