Question

help! Given f(x) = the quantity of 5x plus 1, divided by 2, solve for f-1(8).

Answer 1

f(x)=(5x+1)/2 first find the inverse function, Do you know how to

Answer 2

no

Answer 3

okay, let me explain it then

Answer 4

First you check if the function passes the horizontal line test. in this case it passes the test
since that's the equation of a line

Answer 5

okay

Answer 6

then Do this y=(5x+1)/2
switch x and y you will get
x=(5y+1)/2
then solve for y
2x=5y+1
2x-1=5y
(2x-1)/5=y
now instead of y replace it with f^-1(x)
so f-1(x)=(2x-1)/5

Answer 7

now you can evaluate for f-1(8) by replacing x with 8

Answer 8

so it would be f-1(8)=2(8)-1/5

Answer 9

correct!

Answer 10

I got 79/5

Answer 11

No, because you doing this 2(8) -1/5

Answer 12

(2(8)-1)/5 the whole thing is divided by 5 not only 1

Answer 13

If you pay attention i was using parenthesis so you won't confuse that

Answer 14

oh okay so the answer is 3