document.write( "Question 429413: Please help me set this up in an equations and solve. I am terrible at word problems.
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Algebra.Com's Answer #298246 by Edwin McCravy(20055)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "The other tutor's solution is wrong\r\n" );
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\n" ); document.write( "Flying with the wind, a small plane travels 150 miles in 2 hours. Against the wind, it took 3 hours to travel the same distance. Find the speed of the wind.
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document.write( "Two ways to do it:\r\n" );
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document.write( "1.  In your head with no algebra\r\n" );
document.write( "2.  Using algebra\r\n" );
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document.write( "1. In your head:\r\n" );
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document.write( "It took the plane a total of 5 hours to go 300 miles.  It gained\r\n" );
document.write( "the same amount of time flying with the wind as it lost flying \r\n" );
document.write( "against it, so it is the same as if it went 300 miles with no \r\n" );
document.write( "wind, so in still air the plane can fly 300÷5 or 60mph.  Since \r\n" );
document.write( "it went 150 miles in 2 hours, that was 75 miles per hour.  So \r\n" );
document.write( "the wind increased its speed by 15 mph, so that's the speed of \r\n" );
document.write( "the wind.  Answer: 15mph.\r\n" );
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document.write( "2.  Using algebra:\r\n" );
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document.write( "Make this chart\r\n" );
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document.write( "                    Distance      Rate      Time\r\n" );
document.write( "With the wind         \r\n" );
document.write( "Against the wind      \r\n" );
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document.write( "We are given the distances and the times, so fill those in\r\n" );
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document.write( "                    Distance      Rate      Time\r\n" );
document.write( "With the wind          150                    2\r\n" );
document.write( "Against the wind       150                    3\r\n" );
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document.write( "Let x = the speed of the plane in still air:\r\n" );
document.write( "Let y = the speed of the wind.\r\n" );
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document.write( "Flying with the wind, the speed is found by adding the wind's\r\n" );
document.write( "speed to the plane's, or x+y\r\n" );
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document.write( "Flying against the wind, the speed is found by subtracting the\r\n" );
document.write( "wind's speed from the plane's, or x-y.\r\n" );
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document.write( "Fill those in:\r\n" );
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document.write( "                    Distance      Rate      Time\r\n" );
document.write( "With the wind          150        x+y         2\r\n" );
document.write( "Against the wind       150        x-y         3\r\n" );
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document.write( "Now use Distance = (Rate)(Time)\r\n" );
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document.write( "            150 = (x+y)(2)\r\n" );
document.write( "            150 = (x-y)(3)\r\n" );
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document.write( "            150 = 2(x+y)\r\n" );
document.write( "            150 = 3(x-y)\r\n" );
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document.write( "            150 = 2x + 2y\r\n" );
document.write( "            150 = 3x - 3y\r\n" );
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document.write( "Divide the first equation through by 2\r\n" );
document.write( "Divide the second equation through by 3\r\n" );
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document.write( "             75 = x + y\r\n" );
document.write( "             50 = x - y\r\n" );
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document.write( "Add the two equations term by terms:\r\n" );
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document.write( "            120 = 2x\r\n" );
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document.write( "Divide by sides by 2\r\n" );
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document.write( "             60 = x\r\n" );
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document.write( "So the plane goes 60mph in still air.\r\n" );
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document.write( "Substitute x=60 in one of the equations, say the\r\n" );
document.write( "first one:\r\n" );
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document.write( "            75 = x + y\r\n" );
document.write( "            75 = 60 + y\r\n" );
document.write( "            15 = y\r\n" );
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document.write( "Edwin
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