Question 36026
The ffreight train travels at x mph
The express train travels at 20+x mph
Equation:
{{{300/x-280/(x+20)=2}}}
300(x+20)-280(x)=2[(x)(x+20)]
20x+6000=2(x^2+20x)
2x^2+40x-20x-6000=0
x^2+10x-3000=0
Can you solve that you get x=50
50+20=70
Hence, the speed of the freight train is 50mph and the speed of the express train is 70mph.
Paul.