document.write( "Question 805302: Flying to Kampala with a tailwind a plane averaged 158 km/h. On the return trip the plane only averaged 112 km/h while flying back into the same wind. Find the speed of the wind and the speed of the plane in still air.
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Algebra.Com's Answer #485172 by mananth(16946)\"\" \"About 
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x= Plane speed in still air
\n" ); document.write( "y= wind speed
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\n" ); document.write( "1 x + 1 y = 158 .............1
\n" ); document.write( "Total value
\n" ); document.write( "1 x -1 y = 112 .............2
\n" ); document.write( "Eliminate y
\n" ); document.write( "multiply (1)by 1
\n" ); document.write( "Multiply (2) by 1
\n" ); document.write( "1 x y = 158
\n" ); document.write( " x - y = 112
\n" ); document.write( "Add the two equations
\n" ); document.write( "2 x = 270
\n" ); document.write( "/ 2
\n" ); document.write( "x = 135
\n" ); document.write( "plug value of x in (1)
\n" ); document.write( "1 x + 1 y = 158
\n" ); document.write( "135 + y = 158
\n" ); document.write( " y = 158 -135
\n" ); document.write( " y = 23
\n" ); document.write( " y = 23
\n" ); document.write( "x= 135 Plane speed in still air 135
\n" ); document.write( "y= 23 wind speed 23
\n" ); document.write( "m.ananth@hotmail.ca
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