document.write( "Question 591501: A bird flew 12 miles in an hour aided by a tailwind. Then it turned and flew back against the wind but was unable to fly only 4 miles per hour. What was the speed of the wind? How fast would the bird have flown if there had been no wind? \n" ); document.write( "

Algebra.Com's Answer #375650 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
Let $\"+s+\"$ = the bird's speed with no wind
\n" ); document.write( " $\"+s+%2B+w+\"$ = bird's speed going with the wind
\n" ); document.write( " $\"+s+-+w+\"$ = bird's speed going against the wind
\n" ); document.write( "------------
\n" ); document.write( "going with the wind:
\n" ); document.write( " $\"+12+=+%28+s+%2B+w+%29%2A1+\"$
\n" ); document.write( "going against the wind:
\n" ); document.write( " $\"+s+-+w+=+4+\"$
\n" ); document.write( " $\"+s+=+4+%2B+w+\"$
\n" ); document.write( "By substitution:
\n" ); document.write( " $\"+12+=+%28+4+%2B+w+%2B+w+%29%2A1+\"$
\n" ); document.write( " $\"+12+=+4+%2B+2w+\"$
\n" ); document.write( " $\"+2w+=+12+-+4+\"$
\n" ); document.write( " $\"+2w+=+8+\"$
\n" ); document.write( " $\"+w+=+4+\"$
\n" ); document.write( "and
\n" ); document.write( " $\"+s+=+4+%2B+w+\"$
\n" ); document.write( " $\"+s+=+4+%2B+4+\"$
\n" ); document.write( " $\"+s+=+8+\"$
\n" ); document.write( "The speed of the wind is 4 mi/hr
\n" ); document.write( "The speed of the bird with no wind is 8 mi/hr \n" ); document.write( "

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