### Home > A2C > Chapter 4 > Lesson 4.3.1 > Problem4-135

4-135.

For each quadratic function below, use the idea of completing the square to write it in graphing form. Then state the vertex of each parabola. 8-106 HW eTool (CPM). Homework Help ✎

1. $f(x)=x^2+6x+15$

Set up tiles to reflect the problem.

Write an equivalent equation using the tile arrangement.

$f(x)=(x+3)^2+6$, vertex at $(−3, 6)$

1. $y=x^2−4x+9$

Refer to part (a.)

1. $f(x)=x^2+8x$

You will need to add and subtract the same number of tiles on the right side of the equation in order to complete a square.

1. $y=x^2+5x−2$

You will need to add and subtract the same number of tiles on the right side of the equation in order to complete a square.

Use the eTool below to help complete these problems.
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