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#1 2014-08-01 13:49:54

emsfontya
Guest

help pleaseeeee

#9 - Not answered

#13 - Can be factored further

#15 - Incorrect.  Does (x+3)(x+3)=x2 + 9?



I need help with the following.


#9. Divide 15x7 ¨C 45x5 / 3x4






#13. Factor 4x6 ¨C 16x2 using the difference of squares method. Be sure to factor completely and show your work. If this is not possible for some reason, state why.


4x^6-16x^2=(2x^3-4x)(2x^3+4x)





#15. Factor x2 + 9 using any method you choose. Show your work. If this is not possible for some reason, state why.

x^2=x*x
9=3*3
(x^2+9)
(x+3)(x+3)

#2 2014-08-01 21:26:01

Bob
Administrator
Registered: 2010-06-20
Posts: 10,058

Re: help pleaseeeee

hi emsfontya

Welcome to the forum.

The layout of some of your work is unclear.  I'll help as much as I can.

Q15.

(x+3)(x+3) = x^2 + 6x + 9

http://www.mathsisfun.com/algebra/facto … atics.html

a = 2;   b = 0;   c = 9

So this quadratic has no real solutions.  It can be factored using complex numbers, but I suspect your course has not introduced these yet.

Q13 I'm seeing a stray 'C' in your algebra.  I'll assume the following:

Have a look at

http://www.mathsisfun.com/definitions/d … uares.html

Q9

Very hard to make out the question here.  Is it

You can invert the denominator and multiply

Now you can cancel common factors.

Bob


Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob smile

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