Answer:

Step-by-step explanation:
We want to simplify:

We rewrite as positive index to get:

This simplifies to

This will finally give us:

We cannot simplify further.
Hence the simplest form is 
X = 5 or x = 13.
If you need details, please ask!
Answer:
x= 942.22
Step-by-step explanation:
.9x-18=830
.9x=848
x=942.222222222
which will be x= 942.22
Is this chemistry, their are many apps online that do you it automatically for u
210:1260
If simplified it is
1:6
If Hope this helped if any question feel free to ask!! :D