I really need help with these!!!!

Question

 
Find the inverse function for f(x) = 2x + 5. 
 

f^-1(x) = (x + 5) / 2

f^-1(x) = x/2 - 5

f^-1(x) = 2(x - 5)

f^-1(x) = 2x - 5

f^-1(x) = (x - 5) / 2
 

Find the inverse function for f(x) = 4x - 9. 
 

f^-1(x) = x/4 + 9

f^-1(x) = (x - 9) / 4

f^-1(x) = 4x + 9

f^-1(x) = (x + 9) / 4

f^-1(x) = 4(x + 9)
 
Find the inverse function for f(x) = 3 - 2x. 
 

f^-1(x) = 2(3 - x)

f^-1(x) = (x - 3) / 2

f^-1(x) = (3 - x) / 2

f^-1(x) = 3 - x/2

f^-1(x) = 3 - 2x

Answer 1

For each question, since they are the same, switch places with x and y.  Then solve for y.  For example,  if I have an equation such that

  

y = mx + b

 

 

Then switching places with x and y would yield

 

x = my + b

 

 

Then you would simply solve for y from the newly formed equation.  Follow the steps that I gave here to find the inverse for each specific function.