document.write( "Question 53582: i'm having problems solving for specific variables. The problem is \r
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Algebra.Com's Answer #35838 by AnlytcPhil(1810)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "I'm having problems solving for specific variables. The \r\n" );
document.write( "problem is \r\n" );
document.write( "x/x+a = b/a, where I need to solve for x. \r\n" );
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document.write( "                         x       b\r\n" );
document.write( "                      ------- = ---\r\n" );
document.write( "                       x + a     a\r\n" );
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document.write( "Cross multiply. I will explain. It is\r\n" );
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document.write( "(Upper left expression) times (lower right expression)\r\n" );
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document.write( "                        equals \r\n" );
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document.write( "(upper right expression) times (lower left expression.)\r\n" );
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document.write( "Upper left expression = x\r\n" );
document.write( "Lower right expression = a\r\n" );
document.write( "Upper right expression = b\r\n" );
document.write( "Lower left expression = (x + a)\r\n" );
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document.write( "So the next equivalent equation is\r\n" );
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document.write( "                        (x)(a) = (b)(x + a)\r\n" );
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document.write( "Don't need all those parentheses\r\n" );
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document.write( "                            xa =  b(x + a)\r\n" );
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document.write( "Use the distributive principle to remove the\r\n" );
document.write( "parentheses on the right:\r\n" );
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document.write( "                            xa = bx + ba\r\n" );
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document.write( "Get rid of the x term on the right side by\r\n" );
document.write( "adding -bx to both sides:\r\n" );
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document.write( "                            xa = bx + ba\r\n" );
document.write( "                           -bx  -bx\r\n" );
document.write( "                        -------------------\r\n" );
document.write( "                       xa - bx =      ba\r\n" );
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document.write( "Factor out x on the left by using the distributive \r\n" );
document.write( "principle in reverse\r\n" );
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document.write( "                       x(a - b) = ba\r\n" );
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document.write( "Divide both sides by (a - b)\r\n" );
document.write( "                           \r\n" );
document.write( "                      x(a - b)       ba\r\n" );
document.write( "                      --------- = ---------\r\n" );
document.write( "                       (a - b)     (a - b)\r\n" );
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document.write( "We can cancel the (a - b)'s on the left\r\n" );
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document.write( "                          1\r\n" );
document.write( "                      x(a - b)       ba\r\n" );
document.write( "                      --------- = ---------\r\n" );
document.write( "                        (a - b)    (a - b)\r\n" );
document.write( "                          1\r\n" );
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document.write( "So there's just x left on the left\r\n" );
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document.write( "                                     ba\r\n" );
document.write( "                              x = ---------\r\n" );
document.write( "                                   (a - b)\r\n" );
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document.write( "To make the answer look better change the ba to ab\r\n" );
document.write( "(alphabetical order) and drop the parentheses on \r\n" );
document.write( "the bottom:\r\n" );
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document.write( "                                     ab\r\n" );
document.write( "                              x = ---------\r\n" );
document.write( "                                    a - b\r\n" );
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document.write( "Edwin
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