Answer:
25km/hr (take the word train as bus )
Step-by-step explanation:
Answer
Let x km/hr be the constant speed of the train,
Then Time taken to cover 300km=
x
300
hrs
Time taken to cover 300km when the speed is increased by 5km/hr=
x+5
300
hours
It is given that the time to cover 300km is reduced by 2 hours
∴
x
300
−
x+5
300
=2
⇒
x(x+5)
300(x+5)−300x
=2⇒2x
2
+10x=1500
⇒x
2
+5x−750=0⇒x
2
+30x−25x−750=0
⇒(x+30)(x−25)=0⇒x=25orx=−30
But x cannot be negative. Therefore x=25
Hence, the original speed of the train is 25km/hr
Answer:
![\sqrt[7]{y}](https://tex.z-dn.net/?f=%5Csqrt%5B7%5D%7By%7D)
Step-by-step explanation:
The rule for a fraction as an exponet is:
![a^{\frac{b}{c}}=\sqrt[c]{x^b}](https://tex.z-dn.net/?f=a%5E%7B%5Cfrac%7Bb%7D%7Bc%7D%7D%3D%5Csqrt%5Bc%5D%7Bx%5Eb%7D)
Apply the rule to the expression given:
![y^{\frac{1}{7}}=\boxed{\sqrt[7]{y}}](https://tex.z-dn.net/?f=y%5E%7B%5Cfrac%7B1%7D%7B7%7D%7D%3D%5Cboxed%7B%5Csqrt%5B7%5D%7By%7D%7D)
Hope this helps you.
if x^2=40 you would need to square root both sides to get x alone therefore x=6.3