A. The distance between two places B is 20km. Party A and Party B start from two places a and B respectively. The speed of Party A is 6km / h, and that of Party B is 8km / h A starts half an hour before B starts. How many hours does B start to meet a?

A. The distance between two places B is 20km. Party A and Party B start from two places a and B respectively. The speed of Party A is 6km / h, and that of Party B is 8km / h A starts half an hour before B starts. How many hours does B start to meet a?

(20-3) / (6 + 8) = 1.215h, about 73 minutes

A and B are moving towards each other at a constant speed from a and B, which are 6km apart. They meet one hour later. It is known that a's speed is faster than B's
Fast 1km / h, in order to find out the speed of a, B, please list the corresponding equations?
Who's kind? I'm in a hurry! I'm in a hurry! Thank you first
Do it with binary linear equations! Thank you first!

The velocity of a is a, and the velocity of B is B
a-b=1
a*1+b*1=6
A = 7 / 2, B = 5 / 2

A. The distance between B and B is 30 km. A and B are in a and B. the speed of a is 6 km / h and that of B is 4 km / h
(1) Party A and Party B set out at the same time and went in the opposite direction. How many hours later will they be 40 km apart?
(2) They are going in the opposite direction. A starts 30 minutes late and asks B to leave a few hours later. They are 48 km apart?

(40-30)/(6+4)=1
(48-30-6*0.5)/(6+4)=1.5

The distance between a and B is 30km. A and B are in AB respectively. The speed of a is 6km / h, and that of B is 4km / h
A and B set out at the same time, facing each other, how many hours to meet?
Party A and Party B start at the same time and go in the same direction. Party B is in the front and Party A is in the back. How many hours can party a catch up with Party B?
Party A and Party B set out at the same time and went in the opposite direction. After a few hours, they were 40 km apart?
Lie equation

1. If we meet after X hours, then 6x + 4x = 30, x = 3
2. Let a catch up with B in Y hours, then 6y = 4Y + 30, y = 15
3. If the distance between two people is 40 km after Z hours, then 6Z + 4Z + 30 = 40, z = 1