document.write( "Question 873649: I need some assistance please.\r
\n" ); document.write( "\n" ); document.write( "Two cities are 1000 miles apart. On the first flight a plane flew into a 50 mph headwind. On the return flight the plane had 50 mph tailwind. The round trip flight was 4.5 hours. What is the average speed of the plane without the wind?
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\n" ); document.write( "B. 450 mph
\n" ); document.write( "C. 375 mph
\n" ); document.write( "D. 325 mph \n" ); document.write( "

Algebra.Com's Answer #527033 by ewatrrr(24785) $\"\"$ $\"About$

You can put this solution on YOUR website!


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document.write( "Hi
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document.write( " t = D/r
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document.write( " 9r^2-2000r -22500 = 0,  r = 450 mph
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document.write( "Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation  (in our case ) has the following solutons:
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document.write( "  For these solutions to exist, the discriminant  should not be a negative number.
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document.write( "  First, we need to compute the discriminant : .
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document.write( "  Discriminant d=16810000 is greater than zero. That means that there are two solutions: .
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document.write( "    Quadratic expression  can be factored:
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document.write( "  Again, the answer is: 450, -5.55555555555556.\n" );
document.write( "Here's your graph:
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