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katringette22
Oct 2, 2007, 08:42 PM
can anyone tell me how to factor :2x2-26x-196

rebel-2
Oct 3, 2007, 04:06 AM
can anyone tell me how to factor :2x2-26x-196
I'm guesing the "2x2" is "2x²"

So.. since the general form of a quadratic is "ax²+bx+c=0" we us the forumula
http://upload.wikimedia.org/math/3/e/a/3ea647783b5121989cd87ca3bb558916.png
-b±√b²-4ac
------------
2a

in this equation 2x²-26x-196
a represents 2
b=-26
c=-196

so apply this to the formula

--26±√[-26²-4X2(-196)]
------------------------
2X2

LOL i hate math but this is correct. I had to reflect back az well. Anyway simplify the above and you should get the answer.

note:
1."--26" means "+26"
2. You will get two values, a "-" value and a "+" value
3. that huge dotted line is just show that "--26±√..." is divided by "2X2"

check this site for more info Quadratic equation - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Quadratic_equation)

katringette22
Oct 3, 2007, 06:27 AM
Thanks for the help . Just woundering is there a way to do the squared on the key board of do I havd to do it in word and paste it here. Thanls

rebel-2
Oct 3, 2007, 07:29 AM
Thanks for the help . Just woundering is there a way to do the squared on the key board of do i havd to do it in word and paste it here. Thanls

Yeah no probs.
To do squared on the keyboard hold "alt" down press 0178 on your numpad.

eaca1234
Nov 29, 2007, 10:12 PM
if you're asking how to factor, don't use the quadratic equation. Your teacher, if anything like mine, will probably get mad at you.
you have to find the set of two numbers that fit both:
a+2b=-26
and ab=-196
a and b being:
(2x+a)(x+b)

katringette22
Nov 29, 2007, 10:16 PM
My teach was fine with it but thanks for the help