Rational Equation

Question

Given half of a rational equation with the points (0,4)(1,2)(3,1) come up with an equation.

PS: The answer is y=4/x+1, but I don't know the process of it

Answer 1

Rational function : f(x) = k / (x +b)

using (0,4) : 4 = k / (0 + b)

using (1,2) : 2 = k / (1 + b)

Equation k from both the above equations:

4b = 2(1+b)

2b = 1 + b

b = 1 put value of b in one of above equation we get k = 4

Ans : final equation y = f(x) = 4 / (x + 1)