In order to sketch quadratic curves, we need to ascertain some critical information about the curve:
- the y-intercept, $(0,c)$ obtained from $ax^2+bx+c$
- the x-intercepts (if any) obtained from solving $ax^2+bx+c=0$
- the turning point $(-h,k)$ obtained from completing the square $a(x+h)^2+k$