Home > INT2 > Chapter 9 > Lesson 9.2.1 > Problem9-57

9-57.

For each quadratic function below, complete the square to write it in graphing form. Then state the vertex and $y$‑intercept of each parabola.

1. $y = x^2 + 6x + 15$

The completed square form is $y = (x + 3)^2 +6$.
Now find the vertex and $y$-intercept.

1. $y = x^2 - 3x + 9$

Find the $y$-intercept by letting $x = 0$.
Don't forget to complete the square.