How to Solve Quadratic Equations

Plug $x$ into the function and, if $f(x)=0$, then $x$ is a zero.

Plug $x$ into the function and, if $f(0)=x$, then $x$ is a zero.

Factor the function into binomials with integer coefficients, and check if $x$ is one of the solutions.

Use the quadratic formula on the function and check if $x$ is one of the solutions.

Graph $f$ and see if the point $(0,x)$ lies on the curve of the function.

Graph $f$ and see if the point $(x,0)$ lies on the curve of the function.