a train covers a distance 90 kilometre at a uniform speed had speed been 15 kilometre per hour more it would have taken 30 minutes less for the journey journey find anal speed of the train
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let speed =x km/hr
time = t hours for cor covering 90km
speed = distance /time
x=90/t
after increasing speed,
x+15=90/(t-0.5)
(x+15)(10t-5)=9
10xt-5x+150t-75=9
10*90-5x+150*(90/x)=84
-5x²+1350-900x=84x
-5x²-984x+1350=0
solve this quadratic in x and get x
if x comes negative then reject answer
MARKAS BRAINLIEST
time = t hours for cor covering 90km
speed = distance /time
x=90/t
after increasing speed,
x+15=90/(t-0.5)
(x+15)(10t-5)=9
10xt-5x+150t-75=9
10*90-5x+150*(90/x)=84
-5x²+1350-900x=84x
-5x²-984x+1350=0
solve this quadratic in x and get x
if x comes negative then reject answer
MARKAS BRAINLIEST
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