Cool math fractal

math image

math image

pre-algebra help lessonsalgebra help lessonsprecalculus / calculus help lessonsmath anxiety survival guidegeometry math artmath and jigsaw puzzlesCoolmath booksother math stuff
math help lessonsmath practice problemsmath gamesmath dictionarygeometry trigonometry reference area
teacher's areaparent's areaCoolmath 4 kidsSpike's Game ZoneFinance FREAKTotally Stressed OutScience Monster
Coolmath Algebra
Factoring Lesson 4 - Trinomials - Undoing FOIL  (page 3 of 9)
---- This algebra lesson explains how to undo FOIL in trinomials.

math image
Now available: Coolmath Algebra books! Part 1, Part 2 and Part 3 covering the Algebra you need from Algebra 1 through Precalculus Algebra (Beginning Algebra through College Algebra)

other Coolmath Books: Coolmath Precalculus Review (the math you really need to survive Calculus 1) and Math Survival Guide (How to conquer math and deal with math anxiety)
line
Graphing Calculator Scientific Calculator << a new window will open for these
line

Let's try another one:

Factor   x^2 + 7x + 12

I'll give you a big start:

( x 3 ) ( x 4 )

What do you think?

The 12 is positive...

and we need a +7...

Will this work?

( x + 3 ) ( x - 4 )

No! It gives a last term of -12.

Will this work?

( x - 3 ) ( x + 4 )

No! Same reason.

What about this?

( x - 3 ) ( x - 4 )

The last term IS a positive 12...

But, the outer and inner terms give -7... So, no!

How about this? (It's our last chance!)

( x + 3 ) ( x + 4 )

Check it with FOIL... It works!

Continued on the next page
 

 The printing and distribution and/or downloading of these lessons is strictly prohibited.
line
Graphing Calculator Scientific Calculator << a new window will open for these
line

.....:::::::::::::::  HELP SUPPORT COOLMATH  :::::::::::::::.....
:::::::  link to us   :::::::   advertise with us  :::::::  why we have ads  :::::::

Thanks for visiting Coolmath.com
© 1997-2010 Coolmath.com, Inc.