I missed class and I am totally lost with these problems. What we have to do is find all real zeros of the function algebraically. My teacher had this equation up on the board but I can;t find it anywhere so any help will help

-bsqaurerooe+-4acdivided by 2a

f(x)=x^2-16

f(x)=t^2-4t^2+4t

g(t)=t^5-6t^3+9t