If g (x) = 3x is graphed on a coordinate plane, what is the y-intercept of the graph?

The y-intercept of the equation of the line is where the graph intersects the y-axis. Further, it is the value of y when x = 0. Substituting this value to the given equation above,

g (x) = y = 3x

y = 3 (0)

Therefore, the value of y is equal to 0.