When the squared term is positive, the parabola opens:

1. The sign of the leading coefficient sets the orientation. 2. A quadratic equation in two variables graphs as a parabola. 3. When the squared term is positive, the parabola opens upward. 4. When the squared term is negative, the parabola opens downward. _Source: OpenStax Elementary Algebra 2e (CC BY 4.0), Ch 10 'Quadratic Equations', sections 10.1-10.5_