PLEASE HELP

[cluelessinmath]

I am having a big problem with this question. i really hope you can help:

Find the inverse of the function and express it in the form y=f-1(x).

x=4y+9

f-1(x)= __________


please help me. i really don't understand this problem at all.

 

[tkhunny]

Find the inverse of the function and express it in the form y=f-1(x).
x=4y+9
f-1(x)= __________

It says y = f^-1(x). Just solve for 'y' and you are done.

x = 4y + 9
x - 9 = 4y
y = ¼(x-9) = f^-1(x)

 

[stapel]

The usual procedure for finding an inverse function is as follows:

____1) Rename "f" as "y".
____2) Solve for "x=".
____3) Switch x and y.
____4) Rename "y" as "f-inverse".

See how far you can get in this process. If you get stuck before completing step (4), please reply showing how far you have gotten. Thank you.

Eliz.