Chapter 3:

Section 3-3 Cramer's Rule
by Jamie D.

Suzie had a birthday party for her 12th birthday.  She invited 10 boys (x) and 12 girls( y).  There was a total of 22 people who came to her party.  For her 13th birthday party, she invited 13 boys (x) and 15 girls (y).  There was a total of 28 people at her party.  The solution for this problem is:

where:

                [E    B]                      [A    E]                        

                [F    D]                      [C    F]                     [A    B]

  X =     _______,          Y = ________,       and   [C    D] cannot equal 0 

               [A    B]                       [A    B]       

               [C    D]                      [C    D]

          [22    12]                   [10    22]

          [28    15]                   [13    28]

   x =  _______,          y = _______     

          [10    12]                   [10    12]                              

          [13    15]                   [13    15]                                

then it becomes: X = 22(15)-(22)(28)

                                  10(15)-(12)(13)

                                 =   -286/-6

                                  = 143/3

Y = 10(28)-(22)(13)

       10(15)-(12)(13)

              = -6/-6

               = 1

So....the solution is (143/3, 1)

Need more help?  Go to these webpages...

 http://www.sparknotes.com/math/algebra2/.dir/                              

        http://home.xnet.com/~fidler/triton/math/review/mat085/mat085.htm

"Rather fail with honor than succeed by fraud."

                                                           ~Sophocles~
                                    http://www.houseofquotes.com/quotes/integrity/

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