Q48 of 70 Page 11

Fill in the blanks in each of the

Let the relation R be defined in N by aRb if 2a + 3b = 30. Then R = ______.

Given that, 2a + 3b = 30


⇒ 3b = 30 - 2a


⇒


Since a,b ∈ N, ‘a’ must be a multiple of 3.


Substituting a = 3 in above equation we get,


⇒


∴ for a = 3, b = 8


Similarly,


For a = 6, b = 6


For a = 9, b = 4


For a = 12,b = 2


Thus, R = {(3,8),(6,6),(9,4),(12,2)}


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