The process of (4x + 20) / (x + 20) = 2 solving the equation

The process of (4x + 20) / (x + 20) = 2 solving the equation

(4x+20)/(x+20)=2
(4x+20)/(x+20)-2=0
(4x+20)/(x+20)-2(x+20)/(x+20)=0
（4x+20-2x-40）/（x+20）=0
（2x-20）/(x+20)=0
The denominator is not zero
So the molecule is zero
2x-20=0
2x=20
x=10

4X = x + 9 to solve the equation

Move x to the left=
4x-x=9
3x=9
x=3

Solve the equation 4x = 27

4X of 9 = 27
X = 27 △ 4 / 9
X = 60 and 3 / 4

There are thirty-five chickens and ninety-four rabbits in the same cage

If there are x chickens, there are (35-x) rabbits
2x+4（35-x）=94
The solution is x = 23
35-x=35-23=12
A: there are 23 chickens and 12 rabbits