You can
put this solution on YOUR website!quadratic factorises to
so,
so the roots are either x=4 or x=-4.
As the curve has - x-squared term, it is a n-shape, whose maximum will be at the x-values mid-way between its roots, ie at x=0.
When x=0, y is 16.
So, domain is xeR
range is yeR, y<=16
jon.