document.write( "Question 1128807: A plane flew for 4 hours against a 10mph wind. It then flew for 3 hours with the same wind. In all the plane flew for 1390 miles. Find the rate of the plane in still air \n" ); document.write( "

Algebra.Com's Answer #745320 by ikleyn(52781) $\"\"$ $\"About$

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document.write( "Let x be the plane speed in still air, in miles per hour.\r\n" );
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document.write( "Then the speed with the wind is (x+10) mph, while the speed against the wind is (x-10) mph.\r\n" );
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document.write( "The total distance equation is\r\n" );
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document.write( "    4*(x-10) + 3*(x+10) = 1390   mi,es.\r\n" );
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document.write( "Solve for x.\r\n" );
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