f = {(1, 1), (2, 3), (0, –1), (–1, –3)} and f(x) = ax + b
(1, 1) ∈ f ⇒
f(1) = 1
⇒ a × 1 + b = 1
⇒ a + b = 1 (0, –1) ∈ f
⇒ f(0) = –1 ⇒ a × 0 + b = –1
⇒ b = –1
On substituting b = –1 in a + b = 1,
We obtain a + (–1) = 1 ⇒ a = 1 + 1 = 2.
Thus, the respective values of a and b are 2 and –1.