What should be added to 
so as to get 
?
Suppose x be the rational number to be added to 
to get 
Then,
+ x = 
= 
+ 
x = 
x = 
x = 
Therefore,
The required number x = 
7
What should be added to so as to get ?
Suppose x be the rational number to be added to to get
Then,
+ x =
= +
x =
x =
x =
Therefore,
The required number x =