Q23 of 109 Page 1

Let the relation R be defined on N by a Rb iff 2a + 3b = 30. Then write R as a set of ordered pairs.

Given R = {(a, b) : 2a + 3b = 30} ∀ (a,b) ∈ N


Now according to the question 2a + 3b = 30:


⇒ R={(3,8),(6,6),(9,4),(12,2)}


NOTE: 0 is a whole number that’s why its not considered in this set, Although if we consider 0 as a natural number then the answer would be:


⇒ R={(0,10),(3,8),(6,6),(9,4),(12,2),(15,0)}


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