Write an equation for the linear function f with the given values.

Question

f(1)=3, f(3)=4

Answer 1

you are given 2 points:
(1,3) and (3,4)

find the slope,
m = (4-3)/(3-1) = 1/2

then
y-3 = (1/2)(x - 3)

arrange it into one of the standard ways to write a straight-line
equation.

Answer 2

y=1/2x+3/2