Discuss and answer Exercise 135 as a group.
The equation of a parabola can be determined if three points on the parabola are known. To do so, start with $y=a x^{2}+b x+c$. Then substitute the $x$ - and $y$-coordinates of the first point into the equation. This will result in an equation in $a, b$, and $c$. Repeat the procedure for the other two points. This process yields a system of three equations in three variables. Next, solve the system for $a, b$, and $c$. To determine the equation of the parabola, substitute the values determined for $a, b$, and $c$ into the equation $y=a x^{2}+b x+c$.
Three points on a parabola are $(0,12),(3,-3)$, and $(-2,32)$.
a) Individually, determine a system of equations in three variables that can be used to determine the equation of the parabola. Then compare your answers. If each member of the group does not have the same system, determine why.
b) Individually, solve the system and determine the values of $a, b$, and $c$. Then compare your answers.
c) Individually, write the equation of the parabola passing through $(0,12),(3,-3)$, and $(-2,32)$. Then compare your answers.
d) Individually, write the equation in
$$
y=a(x-h)^{2}+k
$$
form. Then compare your answers.
e) Individually, graph the equation in part d). Then compare your answers.