document.write( "Question 1015563: Kiran drove from Tortula to Cactus, a distance of 240 mi. She increased her speed by 8 mi/h for the 392 mi trip from Cactus to Dry Junction. If the total trip took 12 h, what was her speed from Tortula to Cactus? \n" ); document.write( "

Algebra.Com's Answer #631910 by stanbon(75887) $\"\"$ $\"About$

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Kiran drove from Tortula to Cactus, a distance of 240 mi. She increased her speed by 8 mi/h for the 392 mi trip from Cactus to Dry Junction. If the total trip took 12 h, what was her speed from Tortula to Cactus?
\n" ); document.write( "-------
\n" ); document.write( "T to C DATA::
\n" ); document.write( "dist = 240 miles ; rate = x mph ; time = d/r = 240/x hrs
\n" ); document.write( "--------
\n" ); document.write( "C to D DATA:
\n" ); document.write( "dist = 392 miles ; rate = x+8 mph ; time = d/r = 392/(x+8) hrs
\n" ); document.write( "------
\n" ); document.write( "Equation:
\n" ); document.write( "time + time = 12 hrs
\n" ); document.write( "240/x + 392/(x+8) = 12
\n" ); document.write( "------
\n" ); document.write( "240(x+8) + 392x = 12x(x+8)
\n" ); document.write( "------
\n" ); document.write( "240x + 1920 = 12x^2 + 96x
\n" ); document.write( "------
\n" ); document.write( "2x^2 - 144x - 1920 = 0
\n" ); document.write( "-----
\n" ); document.write( "x^2 - 72x - 960 = 0
\n" ); document.write( "x = 83.5 mph (speed from T to C)
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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