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The Brainliest Answer!
2014-10-29T22:10:54+05:30
Let the speed of the train be x km/h
360/x
=>(360/x+5) + 1
=>360(x+5) = (360+x+5)x
=>360x+1800 = 360x+ x^{2} +5x
=> x^{2} +5x-1800=0
By solving this equation the value of x is 40
Therefore the speed will be 40km/h
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gautam, you may use the equation editor in the brainly - answering browser window - the button Pi gives you that. The square symbol is available - if you click the Omega button in that answering window, you will get many symbols. using these you can write more beautiful answers.
Thanq for the suggesion
And my name is gautami
2014-10-29T22:10:55+05:30

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Distance = 360 km
Let the speed of the train be u  km/h
be the time taken to complete the journey be t₁ hr
so   
distance/speed = time
so     360/u = t₁  ............  ( i )

2nd case

the speed of the train (u + 5) km/h
so time taken  = t₁ - 1 hr

so 360/(u + 5) = t₁ - 1

substituting ( i ) in the equation

\frac{360}{u+5}=\frac{360}{u}-1

\frac{360}{u+5}-\frac{360}{u}=-1

\frac{360u-360u-1800}{u(u+5)}=-1

\frac{1800}{u(u+5)}=1   (cancelling the -1)

1800=u(u+5)

1800=u^{2} +5u

u^{2} +5u-1800=0

u^{2} +45u-40u-1800=0  (doing the middle term factor)

u(u+45)-40(u+45)=0

(u-40)(u+45)=0


so u = - 45 and 40 
so speed can't be negative so the the speed of the train is 40 km/hr

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so no need of doing like that