When graphing quadratic equations, do you include the y-intercept on the graph?

sure, if it exists

For a "vertical " parabola there will always be a y-intercept
For a sideways parabola, there may not be one.

Yes.

When graphing quadratic equations, it is important to include the y-intercept. The y-intercept is the point where the graph intersects the y-axis. It tells us the value of y when x is equal to zero.

To find the y-intercept, we set x equal to zero in the quadratic equation and solve for y. The resulting value of y will be the y-coordinate of the y-intercept. Once we have this point, we plot it on the graph of the quadratic equation.

Including the y-intercept on the graph helps us visualize the behavior of the quadratic equation and understand important features of the graph.