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You can put this solution on YOUR website!
Hopefully you know that you are solving a system of equations here and that you must set up 2 equations with 2 variables.
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document.write( "The first think you need to do is determine what your two variables are, in this case you are selling White Sweatshirts and Yellow Sweatshirts, so...
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document.write( "Let x = the number of White Sweatshirts,
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document.write( "Let y = the number of Yellow Sweatshirts
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document.write( "Now that we know that x and y are the NUMBER OF SWEATSHIRTS SOLD, how many were sold total? 30\r
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document.write( "The other information we have is about the cost, $10 for a White and $12 for a yellow. This next equation is exactly the same way a Cash Register figures out the problem...
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document.write( "10 dollars for every While sweatshirt sold, if you sold 3 you would have 3*10 which is 30 dollars. But since we don't know how many sweatshirts were sold we have to use our variable, so 10 dollars times x number of sweatshirts is 10x.
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document.write( "The same is true for yellow sweatshirts, 12 dollars times y number of yellow is 12x.
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document.write( "When you add the two profits together you should get the total profit, so
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document.write( "Here are you two equations then.
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document.write( "Now use any method you are comfortable with to solve this problem, Substitution, Elimination or the Calculator.
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document.write( "If you are comfortable using matrices and you have a TI 83 or 84 calculator try this method. Under matrix create a 2x3 matrix.
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document.write( "in the first row plug in 1 1 30
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document.write( "in the 2nd row plus in 10 12 344
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document.write( "Quit out and go back to your home screen, Hit the 2nd and then Zero to get to the catalog, hit the times button ( x ) to get to the r's and scroll down to find the rref( function.
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document.write( "Plug in the matrix you just created...
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document.write( "rref([A])
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document.write( "Hit enter, and you should have the answer ...\r
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document.write( "1 0 8
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document.write( "0 1 22\r
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document.write( "There ya go, an answer to your question AND a fun exciting way to use the calculator.
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document.write( "Hope that helps, Mr. C