document.write( "Question 754100: if a girl ran for 3 miles, then decreased her speed by 1 and ran for 4 miles and ran for a total of 96 minutes. what were her 2 speeds/ \n" ); document.write( "

Algebra.Com's Answer #458805 by lwsshak3(11628) $\"\"$ $\"About$

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if a girl ran for 3 miles, then decreased her speed by 1 and ran for 4 miles and ran for a total of 96 minutes. what were her 2 speeds.
\n" ); document.write( "***
\n" ); document.write( "let x=speed during 3-mile run
\n" ); document.write( "x-1=speed during 4-mile run
\n" ); document.write( "travel time=distance/speed
\n" ); document.write( "..
\n" ); document.write( " $\"3%2Fx%2B4%2F%28x-1%29=%2896%2F60%29%28hrs%29\"$
\n" ); document.write( " $\"3%2Fx%2B4%2F%28x-1%29=%288%2F5%29%28hrs%29\"$
\n" ); document.write( "LCD:5x(x-1)
\n" ); document.write( " $\"15x-15%2B20x=8x%5E2-8x\"$
\n" ); document.write( "8x^2-43x+15=0
\n" ); document.write( "(x-5)(8x-3)=0
\n" ); document.write( "x=5
\n" ); document.write( "or
\n" ); document.write( "x=3/8(reject, not reasonable)
\n" ); document.write( "her 2 speeds are 5 mph and 4 mph \n" ); document.write( "

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