document.write( "Question 1103240: A plane travels at a speed of 180 mph in still air . Flying with a tailwind the plane is clocked over a of distance of 900 miles. Flying against a headwind it takes 2 hours longer to complete the return trip. What was the wind velocity? \n" ); document.write( "
Algebra.Com's Answer #717943 by josgarithmetic(39629)\"\" \"About 
You can put this solution on YOUR website!
\"system%28r=180%2Cd=900%2Ch=2%2Cw=unknownWindSpeed%29\"
\n" ); document.write( "h is for time difference\r
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document.write( "                  SPEEDS   TIMES      DISTANCE\r\n" );
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document.write( "WITH WIND          r+w     d/(r+w)      d\r\n" );
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document.write( "AGAINST WIND       r-w     d/(r-w)      d\r\n" );
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document.write( "DIFFERENCE                  h\r\n" );
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\r
\n" ); document.write( "\n" ); document.write( "\"highlight_green%28d%2F%28r-w%29-d%2F%28r%2Bw%29=h%29\"\r
\n" ); document.write( "\n" ); document.write( "Solve for w.\r
\n" ); document.write( "\n" ); document.write( "\"d%28r%2Bw%29-d%28r-w%29=h%28r%5E2-w%5E2%29\"
\n" ); document.write( "\"dr%2Bdw-dr%2Bdw=hr%5E2-hw%5E2\"
\n" ); document.write( "\"hw%5E2%2B2dw-hr%5E2=0\"\r
\n" ); document.write( "\n" ); document.write( "Using general solution for quadratic equation, and not assuming the quadratic would be factorable,\r
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\n" ); document.write( "\n" ); document.write( "\"w=%28-2d%2B-+sqrt%28%282d%29%5E2%2B4h%2Ahr%5E2%29%29%2F%282h%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"w=%28-2d%2B-+sqrt%284d%5E2%2B4h%5E2r%5E2%29%29%2F%282h%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"highlight%28w=%28-d%2B-+sqrt%28d%5E2%2Bh%5E2r%5E2%29%29%2Fh%29\"-------the PLUS form will probably be what you want. Substitute the given values now and evaluate both solutions for w, and decide which makes sense.\r
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\n" ); document.write( "\n" ); document.write( "Substitute the given values into the formula for w, and should find \"highlight%28w=34.7%2A%28miles%2Fhour%29%29\".
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