Is this a function or not a function explain why or why not

What is the distance from zero if a quadratic function has a line of symmetry at x=-3 and a zero at 4

Hello i need with my math homework i don't understand can someone explain how this works

The table below shows the number of color pages a printer prints out over a period of time. printed pages in color time (min), x 2 6 8 18 number of pages, y 3 9 12 27 what is the constant of variation?