A local train has departed from the station A at ten o'clock with the speed of 55 km/h. One and a half of an hour later an express has departed from the station B, which is 360 km far from the station A, and it went toward the local train with the speed of 130 km/h. At what time and how far from the station A will the two trains meet ?

!0.00360 km

><11.30

55km/h                               130 km/h

Step-by-step explanation:

in a one and a half hour the distance between the train will be

360- 55*1,5=277.5 km

in an hour the distance between the trains is less with 55+130=185 km

to meet the trains , the distance between them should be zero

277.5 - 185*x=0

+185 x             +185 x

277.5=185x

x=277.5/185 hours

x= 1.5 hours  after 11.30

They meet at 13.00

the distance will be   55*3 =165 km from the station A

let's cover over the formula of the vertex:

y = a(x – h)^2 + k

in this formula, (h,k) are the vertex, always remember that the positive or negative value of the vertex is based on the sign it has.

for example, if the vertex is -3,-6 then both the x and y value would have the positive sign attached to it and if it were a positive x and y value, then a negative sign would be attached to it.

with that being said, for our problem the x value is a positive one so we are looking for a number with a negative sign next to it, in this case the first and second choice.

however, for the first answer choice it isn't quite part of the formula so we know that the answer choice correctly displays the x value.

to confirm, we can see if the -1 fits correctly with the second answer choice, and as mentioned above a negative number will have a positive sign attached to it. so, for our problem we can see that -1 has been changed to +1, so we can confirm that the second answer choice is correct.

hence, our final answer is y=(x - 1)^2 + 1