1 tàu hỏa đi từ A đến B với quãng đường là 40km . Khi đi đến B , tàu dừng lại 20 phút rồi đi tiếp 30km đến C với vận tốc lớn hơn vận tốc khi đi từ A đến B là 5km/h . Tính vận tốc của tàu khi đi trên quãng đường AB . Biết thời gian kể từ khi tài xuất phát từ A đến khi tới C hết tất cả 2gio

The speed from A to B is 40 km/h.

Step-by-step explanation:

Distance from A to B = 40 km

Distance from B to C = 30 km

Speed from A to B is v km/h

Speed fro B to C is v + 5 .

total time, t = 2 hours

Stopping time at B = 20 minutes

Let the time from A to B is t'.

Let the time from B to C is t''.

The total time is

Speed cannot be negative so the speed from A to B is 450 km/h.

options a,b,c are the right answer.

step-by-step explanation:

a linear parent function is always represented as y = x

if we write this function in the form of y=mx+c

⇒

or  

now if we plot a graph we will find these characteristics:

1) y intercept of the graph is zero so its a straight line passing through origin.

2) as we can see in both the forms of function written, values of x and y may be either positive or negative for the positive slope means points on the graph are either in first quadrant or in third one.

3) it's slope is one.

the 1st digit is in the 100s n its 1

step-by-step explanation:

3,589÷18 = 199.389

so the first digit of the quotient is in the 100s n its 1