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| Question 32044:  I need help but not sure if I had picked the right topic for this. Here are the problems and all have to be factor completely evidently.
 1.x^3-26x^2+48x
 2.x^2-6wy+3xy-2wx
 3.x^2-5x-14
 4.4x^2-36y^2
 5.3x^2-2x-8
 6.24x^2+10x-4
 I am really sorry for putting 6 of these on here but I just do not understand algebra at all. I will appreciate all the help that I can get. Thank you!!!
 Answer by AnlytcPhil(1808)
      (Show Source): 
You can put this solution on YOUR website! 1.  1x3 - 26x2 + 48x
Take out x
x(1x2 - 26x + 48)
Multiply the +48 times the 1 before the x2, getting +48
I. Think of two numbers which
A) multiply to give +48
and which also
B) combine to give -26
It doesn't take long to think of -2 and -24 because
A) -2 TIMES -24 gives +48
and
B) -2 PLUS -24 gives -26
II. Write -26x using -2 and -24
   -26x = -2x - 24x
III. Replace -26x in
   x(x2 - 26x + 48)
   
   with -2x - 24x
   
   x(x2 - 2x - 24x + 48)
IV. Change the parentheses to brackets:
   x[x2 - 2x - 24x + 48]
V. Factor out x in the first two terms in the brackets  
   x[x(x - 2) - 24x + 48]
VI. Factor out -24 in the last two terms in the brackets  
   x[x(x - 2) - 24(x - 2)]
VII. Factor out the common factor (x - 2) within the brackets
   x[(x - 2)(x - 24)]
VIII. Erase the brackets:
   x(x - 2)(x - 24)
------------------------------------ 
2.   x2 - 6wy + 3xy - 2wx
I. We can't factor the first two terms, so we must rearrange terms
   x2 + 3xy - 2wx - 6wy
II. Factor x out of the first two terms   
   x(x + 3y) - 2wx - 6wy 
III. Factor -2w out of the last two terms
   x(x + 3y) - 2w(x + 3y) 
  
IV. Factor out common factor (x + 3y)
   (x + 3y)(x - 2w)
-----------------------------
3.   1x2 - 5x - 14
Multiply the -14 times the 1 before the x2, getting -14
I. Think of two numbers which
A) multiply to give -14
and which also
B) combine to give -5
It doesn't take long to think of -7 and +2 because
A) -7 TIMES +2 gives -14
and
B) -7 PLUS +2 gives -5
II. Write -5x using -7 and +2
   -5x = -7x + 2x
III. Replace -5x in
   x2 - 5x - 14
   with -7x + 2x
   
   x2 - 7x + 2x - 14
IV. Factor x out of the first two terms:
  x(x - 7) + 2x - 14
V. Factor +2 out of the last two terms:
  x(x - 7) + 2(x - 7) 
VI. Factor out common factor (x - 7)  
  (x - 7)(x + 2)
------------------------
4.   4x2 - 36y2
First factor out 4
  4(x2 - 9y2)
Change parentheses to brackets and write each as a perfect square
  4[(x)2 - (3y)2]
This is the difference of two perfect squares
Learn formula: A2 - B2 factors as (A - B)(A + B)
  4[(x) - (3y)][(x) + (3y)]
Remover the inner parentheses
  4[x - 3y][x + 3y]
Change brackets to parentheses
  4(x - 3y)(x + 3y)  
-------------------------------
5.   3x2 - 2x - 8
Multiply the -8 times the 3 before the x2, getting -24
I. Think of two numbers which
A) multiply to give -24
and which also
B) combine to give -2
It doesn't take long to think of -6 and +4 because
A) -6 TIMES +4 gives -24
and
B) -6 PLUS +4 gives -2
II. Write -2x using -6 and +4
   -2x = -6x + 4x
III. Replace -2x in
   3x2 - 2x - 8
   with -6x + 4x
   
   3x2 - 6x + 4x - 8
IV. Factor 3x out of the first two terms:
  3x(x - 2) + 4x - 8
V. Factor +4 out of the last two terms:
  3x(x - 2) + 4(x - 2) 
VI. Factor out common factor (x - 2)  
  (x - 2)(3x + 4)
----------------------------
6.   24x2 + 10x - 4
Take out 2
2(12x2 + 5x - 2)
Multiply the -2 times the 12 before the x2, getting -24
I. Think of two numbers which
A) multiply to give -24
and which also
B) combine to give +5
It doesn't take long to think of +8 and -3 because
A) +8 TIMES -3 gives -24
and
B) +8 PLUS -3 gives +5
II. Write +5x using +8 and -3
   +5x = +8x - 3x
III. Replace +5x in
2(12x2 + 5x - 2)
      
   with +8x - 3x
   
   2(12x2 + 8x - 3x - 2)
IV. Change the parentheses to brackets:
   2(12x2 + 8x - 3x - 2)
V. Factor out 4x in the first two terms in the brackets  
   2[4x(3x + 2) - 3x - 2]
VI. Factor out -1 in the last two terms in the brackets  
   2[4x(3x + 2) - 1(3x + 2)]
VII. Factor out the common factor (3x + 2) within the brackets
   2[(3x + 2)(4x - 1)]
VIII. Erase the brackets:
   2(3x + 2)(4x - 1)
Edwin
AnlytcPhil@aol.com
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