document.write( "Question 519213: A bicycle trip of 90 miles would have taken an hour less if the average speed had been increased by 3mi/h. Find the average speed of the biclycle \n" ); document.write( "
Algebra.Com's Answer #345470 by mananth(16949)\"\" \"About 
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speed x
\n" ); document.write( "speed x - 3
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\n" ); document.write( "Distance = same 90 miles
\n" ); document.write( "original time – time with increased speed =1
\n" ); document.write( "t=d/t
\n" ); document.write( "90/x-90 /(x+3) =1
\n" ); document.write( "LCD= x(x+3 )
\n" ); document.write( "multiply by LCD
\n" ); document.write( "90(x+3)-90x=x(x +3)
\n" ); document.write( "90x+270-90x=X^2 +3x
\n" ); document.write( "270 = 1 x^2 + 3 x
\n" ); document.write( "x^2 + 3 x - 270 = 0
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\n" ); document.write( "a= 1 b= 3 c= -270
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\n" ); document.write( "x1=(-3+sqrt(9-(-1080))/ 2
\n" ); document.write( "= 1089
\n" ); document.write( "x1= 15
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\n" ); document.write( "x2=(3-sqrt(9-(-1080)) / 2
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\n" ); document.write( "x2= -18\r
\n" ); document.write( "\n" ); document.write( "ignore negative\r
\n" ); document.write( "\n" ); document.write( "speed = 15 mph\r
\n" ); document.write( "\n" ); document.write( "m.ananth@hotmail.ca
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