Who can solve this system of linear equations with two variables! x-2/3y=4 y-3=x-4 It's like this: X-2 / 3Y = 4, Y-3 = x + 4

Who can solve this system of linear equations with two variables! x-2/3y=4 y-3=x-4 It's like this: X-2 / 3Y = 4, Y-3 = x + 4

First, the second equation y = x + 7 is solved
The first equation solves 3x-2y = 12, then brings y = X-7 in, finds 3x-2 (X-7) = 12, then x = 26, then y = 33

Solving the first order equations with two variables
The distance between the two places is 280km. It takes 14 hours for a ship to travel downstream and 20 hours for a ship to travel upstream to calculate the ship's velocity and current velocity in still water

Suppose: the speed of the ship in still water is XKM / h, and the water velocity is YKM / h
According to the meaning of the title, the equation is: 14 (x + y) = 280
20（X-Y）=280
After simplification: x + y = 20
X-Y=14
The solution is: x = 17, y = 3
So: the speed of the ship in still water is 17km / h, and the current speed is 3km / h

Simultaneous equations
1.m1v=m1v1+m2v2
2. Half m1v ^ 2 = half m1v1 ^ 2 + half m2v2 ^ 2
Solution V2

V, M1, M2 is known. Find V1, v2m2v2 = m1v-m1v1 = M1 (v-v1) (1) m2v2 ^ 2 = m1v ^ 2-m1v ^ 21 = M1 (V ^ 2-v1 ^ 2) (2) (2) / (1) V2 = V + V1 (3) and substitute (1) m2v + m2v1 = m1v-m1v1v-m2v = m2v1 + m2v1v1 = (m1-m2) V / (M1 + m2) V2 = 2m1v / (m)