for anyone who can do calc.....

[magster88]

ok. i need to find the inverse of f(x)= (5 + 5x)/ (7 - 3x). I know you need to switch x and y and solve for y. but i only got as far as 7x - 3xy - 5 = 5y. and now i don't know how to get y by itself. its probably something really obvious that i'm just completely spacing

Comments

[suninos]

All right, I'll just work this through, even though you've gotten almost to the end, actually:

f(x) = (5+5x)/(7-3x)
So switching x and y:
x = (5+5y)/(7-3y)
x(7-3y) = (5+5y)--multiply denominator to other side
7x - 3xy = 5 + 5y--distribute x on left side
7x - 5 = 5y + 3xy--Isolate variables as much as possible
7x - 5 = y(5 + 3x)--Distributive property, move the common y's out
(7x - 5)/(5 + 3x) = y--Divide other side by what you pulled y out of

[magster88]

OOOOOOOOOOHHHHHHHHHHHH. I got it. THANK YOU SO MUCH!!! you are my calc hero, grady.

[emmaline87]

You disgust me, Maggie.

Just kidding.

At least you always have Grady to help you in your hour of need ^___^

[willturner]

Is it sad that I reall don't understand the problem at all. hmm oh well, thank goodness no calculus for me.

[aichan666]

hey guess what? i won't have to study any math again, ever. yay!