# Is the equation y=x^2 +3 a function?

Nov 20, 2016

#### Answer:

For each $x$-value, there is only one $y$-value.
It is a function.

#### Explanation:

This is the equation of a parabola. It does represent a function.

For any $x$ value you choose, there will be only one $y$ value.

You will not end up with a choice of $y$- values.

If you draw the graph and draw a vertical line anywhere, it will only intersect the parabola once. This is an indication that is is a function.