Help please :)
Find the inverse of the following function:

5/2x -15

Question

Help please :)
Find the inverse of the following function:

5/2x -15

anonymous · Answer

the root is x = 6. @shadly

anonymous · Answer

.....What?? I don't need a root... :/

anonymous · Answer

What are the choices available for your question?

anonymous · Answer

2x-30/5, 2x+30/5, 2/5x+15, or 2/5x-15

anonymous · Answer

I have no idea...
@JA1

anonymous · Answer

...Thanks .-.

ja1 · Answer

Fractions type algebra is not my suit 

@melody16 @tcarroll010

anonymous · Answer

You'll get help in just a second please be patient. :) @shadly

johnweldon1993 · Answer

The inverse of

$$y = \frac{ 5 }{ 2 }x - 15$$

first thing you do is switch the 'x' and the 'y'

$$x = \frac{ 5 }{ 2 }y - 15$$

Now solve for 'y' again...can you do that?

anonymous · Answer

I'm not really sure how which is why I asked the question... I know you have to switxh x and y but im kinda stuck

anonymous · Answer

switch*

johnweldon1993 · Answer

Okay....well as shown above...I have switched them....but now to solve for y again...we need to isolate it

$$x = \frac{ 5 }{ 2 }y - 15$$

Lets start by adding 15 to both sides....now we'll have

$$x + 15 = \frac{ 5 }{ 2 }y$$

Now...we want to get rid of that fraction next to the 'y'....so multiply both sides on the equation by 2/5 (the reciprocal of 5/2)

$$\frac{ 2x + 30 }{ 5 } = y$$

So the inverse of your equation...is

$$y = \frac{ 2x + 30 }{ 5 }$$

or written as

$$y = \frac{ 2 }{ 5 }x + 6$$

anonymous · Answer

ooooh okay... Thank you

johnweldon1993 · Answer

No problem! Now did that make sense?

anonymous · Answer

Yes, a lot XD

johnweldon1993 · Answer

Awesome!