NCERT  Solutions for Class 8 Maths Chapter -6 

NCERT  Solution for Class 8 Maths Chapter – 6  SQUARE AND SQUARE ROOTS EXERCISE – 6.2

Q1. Find the square of the following numbers.

  • 32

Solution:-

 

= ( 30 + 2 ) 2

= (30)2 + (2)2 + 2 x 30 x 2

= 900 + 4 + 120

= 1024

 

  • (35)2

Solution:-

 

= ( 30 + 5 )2

= (30)2 + (5)2 + 2 x 30 x 5

= 900 + 25 + 300

= 1225

 

  • (86)2

Solution:-

 

= ( 90 – 4)2

= (90)2 + (4)2 – 2 x 90 x 4

= 8100 + 16 – 720

= 8116 – 720

= 7396

 

  • (93)2

Solution:-

 

= ( 90 + 3)2

= (90)+ (3)2 + 2 x 90 x 3

= 8100 + 9 + 540

= 8649

 

  • (71)2

Solution:-

 

(70 + 1 )2

(70)2 + (1)2 + 2 x 70 x 1

4900 + 1 + 140

5041

 

  • (46)2

Solution:-

 

( 50 – 4 )2

(50)2 + (4)2 – 2 x 50 x 4

2500 + 16 – 400

2116

 

Q2. Write a Pythagorean triplet whose one number is.

  • 6

Solution:-

 

 

2m = 6

M = 6/2 = 3

M2 -1 = 32 -1 = 9 – 1 = 8

M2 + 1 = 32 + 1  = 9 + 1  = 10

( 6,8,10) is a Pythagorean triplet

 

  • 2m = 14

Solution:-

 

M = 14/2 = 7

M2 – 1 = 72 – 1 = 49 – 1 = 48

M2 + 1 = 72 + 1 = 49 + 1 = 50

(14 , 48 , 50) is not a Pythagorean triplet.

 

  • 2m = 16

Solution:-

 

M = 16/2 = 8

M2 – 1 = 82 -1 = 64 – 1 = 63

M2 + 1 = 82 + 1 = 64 + 1 = 65

(16 , 63 , 65 ) is a Pythagorean triplet.

 

  • 2m = 18

Solution:-

 

M = 18/2 = 9

M2-1 = 92 -1 = 81 -1 = 80

M2 + 1 = 92 + 1 = 81 + 1 = 82

(  18 , 80 , 82 ) is a Pythagorean triplet.

NCERT Solutions for class 7 Science Chapter -9