<PRE><B>Question 811722</B>
Noah drives 40 miles --------------x mph speed. 
50 miles ----------------(x-60) mph,
the entire trip takes 3 hours, 

time part I + time part II=3

40/x + 50/(x-60)= 3

multiply by x(x-60)

40(x-60)+50x=x(x-60)*3

40x-2400+50x=3x^2-180x

3x^2-270x+2400=0

/3
x^2-90x+800=0

x^2-80x-10x+800=0

x(x-80)-10(x-80)=0
(x-80)(x-10)=0
x=80 OR 10

ignore 10
							
Noah drives 40 miles --------------80 mph  
50 miles ----------------20  mph,
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