document.write( "Question 633370: 1.A plane travels from Orlando to Denver and back again. On the five-hour trip from Orlando to Denver, the plane has a tailwind of 40 miles per hour. On the return trip from Denver to Orlando, the plane faces a headwind of 40 miles per hour. This trip takes six hours. What is the speed of the airplane in still air?
\n" ); document.write( "please show work \n" ); document.write( "

Algebra.Com's Answer #398852 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
Let $\"+p+\"$ = the speed of the plane in still air
\n" ); document.write( " $\"+p+%2B+40+\"$ = speed of plane from Orlando to Denver in mi/hr
\n" ); document.write( " $\"+p+-+40+\"$ = speed of plane from Denver to Orlando in mi/hr
\n" ); document.write( "---------
\n" ); document.write( "1st trip:
\n" ); document.write( " $\"+d+=+%28+p+%2B+40+%29%2A5+\"$
\n" ); document.write( "2nd trip:
\n" ); document.write( " $\"+d+=+%28+p+-+40+%29%2A6+\"$
\n" ); document.write( "----------------
\n" ); document.write( "By substitution:
\n" ); document.write( " $\"+%28p+%2B+40+%29%2A5+=+%28+p+-+40+%29%2A6+\"$
\n" ); document.write( " $\"+5p+%2B+200+=+6p+-+240+\"$
\n" ); document.write( " $\"+p+=+440+\"$
\n" ); document.write( "440 mi/hr is the speed of the plane in still air
\n" ); document.write( "check:
\n" ); document.write( " $\"+d+=+%28+440+%2B+40+%29%2A5+\"$
\n" ); document.write( " $\"+d+=+480%2A5+\"$
\n" ); document.write( " $\"+d+=+2400+\"$ mi
\n" ); document.write( "and
\n" ); document.write( " $\"+2400+=+%28+p+-+40+%29%2A6+\"$
\n" ); document.write( " $\"+2400+=+6p+-+240+\"$
\n" ); document.write( " $\"+6p+=+2640+\"$
\n" ); document.write( " $\"+p+=+440+\"$ mi/hr
\n" ); document.write( "OK \n" ); document.write( "

\n" );