document.write( "Question 811722: Noah drives 40 miles at a certain speed. Hitting serious traffic, he is forced to drive at a speed that is 60 mph slower. He drives at this new speed for 50 miles. If the entire trip takes 3 hours, what is his speed during each part of the trip? \n" ); document.write( "
Algebra.Com's Answer #488878 by mananth(16946)![]() ![]() You can put this solution on YOUR website! Noah drives 40 miles --------------x mph speed. \n" ); document.write( "50 miles ----------------(x-60) mph, \n" ); document.write( "the entire trip takes 3 hours, \r \n" ); document.write( "\n" ); document.write( "time part I + time part II=3\r \n" ); document.write( "\n" ); document.write( "40/x + 50/(x-60)= 3\r \n" ); document.write( "\n" ); document.write( "multiply by x(x-60)\r \n" ); document.write( "\n" ); document.write( "40(x-60)+50x=x(x-60)*3\r \n" ); document.write( "\n" ); document.write( "40x-2400+50x=3x^2-180x\r \n" ); document.write( "\n" ); document.write( "3x^2-270x+2400=0\r \n" ); document.write( "\n" ); document.write( "/3 \n" ); document.write( "x^2-90x+800=0\r \n" ); document.write( "\n" ); document.write( "x^2-80x-10x+800=0\r \n" ); document.write( "\n" ); document.write( "x(x-80)-10(x-80)=0 \n" ); document.write( "(x-80)(x-10)=0 \n" ); document.write( "x=80 OR 10\r \n" ); document.write( "\n" ); document.write( "ignore 10 \n" ); document.write( " \n" ); document.write( "Noah drives 40 miles --------------80 mph \n" ); document.write( "50 miles ----------------20 mph, \n" ); document.write( " \n" ); document.write( " |