Answer:
Well. this is kinda trivial.
For a function f(x) = y.
The y-intercept is defined as the point where the graph of f(x) intersects the x-axis.
This always happens at x = 0.
So the y-intercept is equal to f(0).
Now, if we have the graph of f(x), you simply can see at what value of y does the graph intersect the x-axis, and that will be the y-intercept.
