document.write( "Question 499760: a woman travels 185 miles by car in 3 hours and 30 minutes. she drives at 50mph for part of the trip and 55mph for the remainder of the trip. How many miles does she travel at 50mph? I can draw a graph and estimate that she drove 1.5 hours at 50 mph leaving 2 hours to drive at 55mph which totals 185 miles traveled, but i don't know how to set up an algebraic problem to solve it. I'm helping my daughter with her algebra.
\n" ); document.write( " \n" ); document.write( "

Algebra.Com's Answer #337842 by oberobic(2304) $\"\"$ $\"About$

You can put this solution on YOUR website!
d = rt is the basic distance equation.
\n" ); document.write( "d = 185
\n" ); document.write( ".
\n" ); document.write( "t = 3 hr 30 min = 3.5 hr
\n" ); document.write( ".
\n" ); document.write( "x = time spent driving at 50
\n" ); document.write( "(3.5-x) = time spent driving at 55
\n" ); document.write( ".
\n" ); document.write( "So,
\n" ); document.write( "50x + 55(3.5-x) = 185
\n" ); document.write( ".
\n" ); document.write( "50x + 192.5 - 55x = 185
\n" ); document.write( ".
\n" ); document.write( "-5x = -7.5
\n" ); document.write( ".
\n" ); document.write( "x = 1.5 hr driving at 50
\n" ); document.write( ".
\n" ); document.write( "3.5-x = 3.5 - 1.5 = 2 hr driving at 55
\n" ); document.write( ".
\n" ); document.write( "Done. \n" ); document.write( "

\n" );