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

Algebra ->  Algebra  -> Quadratic-relations-and-conic-sections -> Lesson Graphing Quadratic Equations (Parabolas) -- Easy as 1-4-9      Log On

Ad: Algebrator™ solves your algebra problems and provides step-by-step explanations!
Ad: Algebra Solved!™: algebra software solves algebra homework problems with step-by-step help!

   

This Lesson (Graphing Quadratic Equations (Parabolas) -- Easy as 1-4-9) was created by by MLipsky(9) About Me : View Source, Show
About MLipsky: Math Teacher, Tutor

Graph Parabolas — easy as 1-4-9


Example: Graph


The vertex is
Okay, the vertex is at (1, ?).
How do I find the y-coordinate?
Plug in x.



So, the vertex is at (1, -10).

Now here's a trick you won't find in your math book.


You can graph the rest of the function in less than a minute, using the 1-4-9 method. Here's how:
From the vertex,
move right 1,
move up 1a.



From the vertex,
move right 2,
move up 4a.



From the vertex,
move right 3,
move up 9a.



Reflect points
to the left,
& graph parabola.

You can use the 1-4-9 method to graph any quadratic equation. It's fast, it's easy, and it works every time!


Courtesy of Michael Lipsky, experienced teacher and tutor.
Algebra, Geometry, Basic Math, and Precalculus
In-Person, Online, or by E-mail
(954) 560-1646,
MathLocker.com


This lesson has been accessed 2382 times.