# How do you find the important parts of the equation to graph the function y= x^2-x-3?

Jul 2, 2018

$\frac{- b}{2 a}$ gives the axis of symmetry

$\frac{- - 1}{2 \times 1}$

$\frac{1}{2}$

So $x = \frac{1}{2}$ is the line of symmetry

Put $x = \frac{1}{2}$ into the equation

$y = {\left(\frac{1}{2}\right)}^{2} - \frac{1}{2} - 3$

$y = - 3 \frac{1}{4}$

The vertex is $\left(\frac{1}{2} , - \frac{13}{4}\right)$

We know it is a $\cup$ shaped parabola with a y intercept (0,-3)

Put a couple of values for X into the equation and plot the coordinates then found.