Answer:
m=-4
Step-by-step explanation:
5m-10m=-10m+5m=-(10m-5m)=-5m=20
divide by 5 on both sides, -m=4
miltiply by -1 on both sides, m=-4
I believe the answer is x+20.
Answer: 
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Work Shown:

Explanation:
In the second step, I multiplied both sides by r to move it to the left side. Then I divided both sides by p to isolate r.
In short, the r and p swap places.
Answer:
f(x) and its inverse are the same
Step-by-step explanation:
<u>The inverse function
</u>
If y=f(x), the inverse function
is defined such as

To find the inverse function, there is a practical method:
a) Change letters x for y and vice-versa
b) Isolate y in terms of x only
c) 
In our case, 
a) Interchanging letters

b) Isolate 
c) 
As we can easily see, f and its inverse are exactly the same
