document.write( "Question 253110: Can you please help me solve this word problem, I have tried multiple times and cannot figure it out, thank you for your help :\r
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\n" ); document.write( "\n" ); document.write( "Two planes start from the same airport and fly in opposite directions. The second plane starts 1/2 hour after the first plane, but its speed is 80 km per hour faster. Find the groundspeed of each plane if 2 hours after the first plane departs the planes are 3200 km apart. \n" ); document.write( "

Algebra.Com's Answer #185341 by Edwin McCravy(20056) $\"\"$ $\"About$

You can put this solution on YOUR website!
Two planes start from the same airport and fly in opposite directions. The second plane starts 1/2 hour after the first plane, but its speed is 80 km per hour faster. Find the groundspeed of each plane if 2 hours after the first plane departs the planes are 3200 km apart.
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document.write( "Make this chart\r\n" );
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document.write( "                 DISTANCE     RATE     TIME\r\n" );
document.write( "first plane        \r\n" );
document.write( "second plane    \r\n" );
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document.write( "Let the rate of the first plane be x\r\n" );
document.write( "Let the rate of the second plane be 80 kph more or x+80\r\n" );
document.write( "Fill those in:\r\n" );
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document.write( "                 DISTANCE     RATE     TIME\r\n" );
document.write( "first plane                    x         \r\n" );
document.write( "second plane                  x+80      \r\n" );
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document.write( "The first plane's time was 2 hours\r\n" );
document.write( "The second plane's time was a half hour less or 2-.5 or 1.5 hours \r\n" );
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document.write( "                 DISTANCE     RATE     TIME\r\n" );
document.write( "first plane                    x         2\r\n" );
document.write( "second plane                  x+80      1.5\r\n" );
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document.write( "Use D=RT to fill in the distances\r\n" );
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document.write( "                 DISTANCE     RATE     TIME\r\n" );
document.write( "first plane         2x         x         2\r\n" );
document.write( "second plane     1.5(x+80)    x+80      1.5\r\n" );
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document.write( "They are 3200 km apart, so the sum of their distances\r\n" );
document.write( "equals 3200\r\n" );
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document.write( "                2x + 1.5(x+80) = 3200\r\n" );
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document.write( "Can you solve that? If both post again asking how:\r\n" );
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document.write( "Answer: x=880 \r\n" );
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document.write( "The first plane was traveling 880 kph and the second \r\n" );
document.write( "plane was traveling 80kph faster or 960 kph.\r\n" );
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document.write( "Edwin

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