Ncert Solutions For Class 8 Maths Ex 4.3

Ncert Solutions For Class 8 Maths Chapter 4 Ex 4.3

Question 1:

 Construct the quadrilaterals.

(i) Quadrilateral EROM

Side MO = 6cm

Side OR = 4.5cm

M=60

O=105

R=105

(ii)Quadrilateral NALP

PL = 4cm

LA = 6.5cm

P=90

A=110

N=85

(iii)Parallelogram RAEH

EH = 5cm

AE = 6cm

R=85

(iv) Rectangle YAKO

KO = 7cm

AK = 5cm

 

Answer:

(i)

(1) Sketch the figure of the quadrilateral

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(2) Using the geometry tools draw the line segment OM 6cm and an angle of 105 at point O. As vertex R is 4.5cm away from the vertex O, cut a line segment RO of 4.5cm from this ray.

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(3) Again, draw an angle of 105 at point R.

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(4) Draw an angle of 60 at point M. Extend this ray so that it meets the previously drawn from R at point E.

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EROM is the desired quadrilateral.

 

(ii)

(1) Total sum of the interior angles of quadrilateral is 360

In quadrilateral NALP, P+L+A+N=360

90+L+110+85=360 285+L=360 L=360285=75

(2)Draw a rough diagram of quadrilateral

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(3) Construct a line PL of 4cm and draw an angle of 75 at point L. As vertex A is 6.5cm away from vertex L, cut a line segment LA of 6.5cm from this ray.

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(4) Draw another angle of 110 at point A.

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(5) Construct an angle of 90 at point P. This line will meet touch the previously drawn ray from A at point N.

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NALP is the required quadrilateral

 

(iii)

(1)Sketch a rough diagram of this quadrilateral as follows

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(2)Construct a line segment EH of 5cm and an angle 85 at point E. As vertex A is at a distance of 6cm and 5cm, draw arcs from point H and A respectively. These will be intersecting each other at point R.

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(3) Vertex H and A are 6 and 5cm away from vertex R. By taking radius as 6cm and 5cm, draw arcs from point H and A respectively. These will be intersecting each other at point R.

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(4) Join H and A with point R

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RAEH is the desired quadrilateral.

 

(iv)

(1) Draw a rough diagram of this quadrilateral as follows.

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(2) Construct a line segment KO of 7cm and an angle of 90 at point K. As vertex A is 5cm away from vertex K, cut a line segment AK of 5cm from this ray.

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(3) Draw two arcs of radius 5 cm from points O and K respectively. These arcs intersect at Y and A.

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(4) Join AY

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It is the desired rectangle YAKO