Question

I need helping solving an equation step-by-step.

Answer 1

\[f ^{-1}(3)\] when \[f(x)=\frac{ 2x+3 }{ 5 }\]

Answer 2

First replace f(x) with y

Answer 3

okay

Answer 4

Then switch x and y.

Answer 5

After that you need to solve for y

Answer 6

okay, but how when i have 2 variables?

Answer 7

well okay, would i multiply x by 5?

Answer 8

do i get \[\frac{ 5x-3 }{ 2 } = y\]

Answer 9

What you should have before doing any math is
\[x=\frac{ 2y+3 }{ 5 }\]
You need to multiply both sides by 5 to get rid of the fraction

Answer 10

After I switch them and solve for y, does y = 5x-2/2

Answer 11

the -2 should be a -3. Other than that it is right

Answer 12

oh i'm sory that's what i meant..

Answer 13

but once i solve for y what do i do when \[f ^{-1}=3\]

Answer 14

you just plug 3 in as x and solve

Answer 15

okay ty

Answer 16

your welcome