When does a parabola open upward

y=ax^2+bx+c

When "a" is positive, opens upward.

When "a" is negative, opens downward.

If the x is squared, the parabola is vertical (opens up or down). If the y is squared, it is horizontal (opens left or right). If a is positive, the parabola opens up or to the right. If it is negative, it opens down or to the left.