document.write( "Question 597471: A cruise ship made a trip of 140 mi in 8 h. The ship traveled the first 60 mi at a constant rate before increasing its speed by 5 mph. Then it traveled another 80 mi at the increased speed. Find the rate of the cruise ship for the first 60 mi. \n" ); document.write( "
Algebra.Com's Answer #378218 by lwsshak3(11628)\"\" \"About 
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A cruise ship made a trip of 140 mi in 8 h. The ship traveled the first 60 mi at a constant rate before increasing its speed by 5 mph. Then it traveled another 80 mi at the increased speed. Find the rate of the cruise ship for the first 60 mi.
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\n" ); document.write( "let x=rate of speed for first 60 mi
\n" ); document.write( "(x+5)=rate of speed for remaining 80 mi
\n" ); document.write( "travel time=distance/speed
\n" ); document.write( "..
\n" ); document.write( "60/x+80/(x+5)=8
\n" ); document.write( "LCD: x(x+5)
\n" ); document.write( "60(x+5)+80x=8x(x+5)
\n" ); document.write( "60x+300+80x=8x^2+40x
\n" ); document.write( "8x^2-100x-300=0
\n" ); document.write( "divide by 4
\n" ); document.write( "2x^2-25x-75=0
\n" ); document.write( "(2x+5)(x-15)=0
\n" ); document.write( "2x+5=0
\n" ); document.write( "x=-5/2 (reject, x>0)
\n" ); document.write( "x-15=0
\n" ); document.write( "x=15
\n" ); document.write( "ans:
\n" ); document.write( "rate of speed of the cruise ship for first 60 mi=15 mph \n" ); document.write( "
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