The coefficient of $\displaystyle{{x}}^{{2}}\usepackage{cmbright}\Huge\$ in this function is an even number, but whether a is odd or even has no effect on the direction in which the graph opens. It is whether a is positive or negative that determines if the graph will open up or down. The correct answer is: Down, because a (the coefficient of $\displaystyle{{x}}^{{2}}\usepackage{cmbright}\Huge\$ ) is negative.