Algebra.Com's Answer #811281 by ikleyn(52781)![\"\"](\"/images/stars/stars-13.gif\")  
You can put this solution on YOUR website!
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document.write( "Could you please show me the steps to the solution of this problem:
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document.write( "Gabrielle rows a boat downstream for 192 miles. The return trip upstream took 8 hours longer.
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document.write( "If the current flows at 2 mph, how fast does Gabrielle row in still water?
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document.write( " The setup equation in the post by @josgarithmetic is incorrect.\r
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document.write( " The best what you can do with his post is to IGNORE it.\r
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document.write( " I came to bring the correct solution and describe the setup and steps clearly and in detailed way.\r
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document.write( "Ler \"r\" be the rate Gabrielle rows in still water (in miles per hour).\r\n" );
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document.write( "Then the effective rate downstream is (r+2) miles per hour and the time rowing downstream is  hours.\r\n" );
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document.write( "The effective rate upstream is (r-2) miles per hour and the time rowing downstream is  hours.\r\n" );
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document.write( "The difference of times is 8 hours, according to the condition. It gives you this time equation\r\n" );
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document.write( " - = 8 hours.\r\n" );
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document.write( "or, dividing both sides by 8, for simplicity\r\n" );
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document.write( "  -  = 1.\r\n" );
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document.write( "To solve this equation, multiply both sides by (r-2)*(r+2) = r^2 - 4. You will get\r\n" );
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document.write( " 24*(r+2) - 24*(r-2) = r^2 - 4.\r\n" );
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document.write( "Simplify step by step\r\n" );
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document.write( " 24r + 48 - 24r + 48 = r^2 - 4\r\n" );
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document.write( " r^2 = 48 + 48 + 4 = 100\r\n" );
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document.write( " r =  = 10.\r\n" );
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document.write( "The problem is just solved.\r\n" );
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document.write( "The ANSWER is: the speed Gabrielle rows in still water is 10 miles per hour.\r\n" );
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document.write( "Let's CHECK. (in such problems, checking is very educative part of the solution.\r\n" );
document.write( " When you check, your understanding of the problems becomes MUCH BETTER (!) )\r\n" );
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document.write( " The time rowing downstream is  =  = 16 hours.\r\n" );
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document.write( " The time rowing upstream is  =  = 24 hours.\r\n" );
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document.write( " The difference of times is 24 hours - 16 hours = 8 hours, exactly as stated in the problem.\r\n" );
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document.write( "Thus we checked and found out that the answer is CORRECT (!)\r\n" );
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document.write( "Solved and carefully explained.\r
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document.write( "@josgaritmetic made changes in his post after seeing my solution.\r
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