How to solve the equation of 100-x = 2x-5

How to solve the equation of 100-x = 2x-5


1. Transfer, get
-x-2x=-105
Merge the similar items to get
-3x=-105
Divide both sides by - 3 to get
x=35



0.1 / 0.01 = 100 / x, how to solve this equation


0.1/0.01=100/x
0.1x=0.01*100
0.1x=1
x=10