Lesson Graphing Quadratic Equations (Parabolas) -- Easy as 1-4-9

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<font face="Verdana"><h1 align="center">Graph Parabolas &#8212; easy as 1-4-9</h1>
<b>Example: </b>Graph <img src="http://www.mathlocker.com/images/gq1.bmp"><table cellspacing="0" border="1" cellpadding="15" bordercolor="29527A"><tr><td><img src="http://www.mathlocker.com/images/gq2.bmp"><br>
The vertex is
<img vspace="4" src="http://www.mathlocker.com/images/gq3.bmp">
<img vspace="4" hspace="16" src="http://www.mathlocker.com/images/gq4.bmp">
<img vspace="4" hspace="16" src="http://www.mathlocker.com/images/gq5.bmp">
<img vspace="4" hspace="16" src="http://www.mathlocker.com/images/gq6.bmp">
</td>
<td>
Okay, the vertex is at (1, ?).
How do I find the y-coordinate?
Plug in x.
<img alt="" vspace="4" src="http://www.mathlocker.com/images/gq7.bmp">
<img alt="" vspace="4" hspace="16" src="http://www.mathlocker.com/images/gq8.bmp">
<img alt="" vspace="4" hspace="16" src="http://www.mathlocker.com/images/gq9.bmp">
<p>So, the vertex is at <span class="answer_box">(1, -10)</span>.</p>
</td><td>
<img alt="" class="problem_image" src="http://www.mathlocker.com/images/quadratic_vertex.png">
</td>
</tr>
</table>
<h2><i>Now here's a trick you won't find in your math book.</i></h2>
You can graph the rest of the function in less than a minute, using the <b>1-4-9 method</b>.  Here's how:
<table cellspacing="0" border="1" cellpadding="15" bordercolor="29527A"><tr><td>From the vertex, 
move right 1, 
move up 1a.<br>
<img alt="" src="http://www.mathlocker.com/images/quadratic1.png">
</td><td>
From the vertex, 
move right 2, 
move up 4a.<br>
<img alt="" src="http://www.mathlocker.com/images/quadratic2.png">
</td><td>
From the vertex, 
move right 3, 
move up 9a.<br>
<img alt="" src="http://www.mathlocker.com/images/quadratic3.png">
</td><td>
Reflect points 
to the left, 
& graph parabola.<br>
<img alt="" src="http://www.mathlocker.com/images/quadratic_parabola.png">
</td>
</tr>
</table>
<p>You can use the <b>1-4-9 method</b> to graph any quadratic equation.  It's fast, it's easy, and it works every time!</p>
<h2 align="center">Courtesy of Michael Lipsky, experienced teacher and tutor.
Algebra, Geometry, Basic Math, and Precalculus
In-Person, Online, or by E-mail
	  (954) 560-1646, 
	  <a href="http://www.mathlocker.com">MathLocker.com</a></h2>