Answer:
x=300
Step-by-step explanation:
Multiply both sides by 10
0.4x·10=0.5x·10-30·10
Refine
4x=5x-300
Subtract 5x from both sides
4x-5x=5x-300-5x
Simplify
-x=-300
Divided both sides by -1
-x/-1=--300/-1
Simplify this and you will get x=300
Hope this Helps