Question

If you are in 7th class open your textbook of maths and then open page no.89 and do 3rd exercise for me and for yourself at least you will learn something.




(NCERT MATH BOOK)​

Answer 1

Answer:

a) 2x+8=12

2x=12-8

2x= 4

x = 4/2

x = 2

b)3(n - 5) = 21

3n-15=21

3n = 21+15

3n = 36

n = 36/3

n = 12

c) 3(n - 5) = -21

3n - 15 = -21

3n = -21 + 15

3n = -6

n = -6/3

n = -2

d) -4(2+x)=8

-8 + (-4x) =8

-8 - 4x = 8

-8 - 8 = 4x

16 = 4x

x = 16/4

x = 4

e) 4(2-x) = 8

8 - 4x= 8

8 - 8 = 4x

0 = 4x

x = 0/4

x = 0