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## #1 2006-10-27 07:58:47

Neha
Member
Registered: 2006-10-11
Posts: 173

### inverse

find the inverse function of
5x - y = 2

so like this

y = 2 - 5x

or i did...

5x - y = 2
subtract 5x both sides
y = -3

5x - (-3) = 2
5x + 3 = 2
subtract 3 both sides
5x = -1
x = -0.2

put the value in both are correct...

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## #2 2006-10-27 08:13:51

Toast
Real Member
Registered: 2006-10-08
Posts: 1,321

### Re: inverse

hmm, not quite

Also, you made a mistake when subtracting 5x from both sides - you also subtracted 5 from 2 to get -3. 5x and 2 aren't like terms though.

With an equation like yours with 2 or more variables (in this case x and y) you can't solve them with the help of only 1 equation. The furthest you can get is

or

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## #3 2006-10-27 08:23:22

Neha
Member
Registered: 2006-10-11
Posts: 173

### Re: inverse

ok thanks...
i was there but messed up a bit i see that.

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## #4 2006-10-27 08:46:46

Neha
Member
Registered: 2006-10-11
Posts: 173

### Re: inverse

orrrrrrrrrrrrrrrrrrrrrrrrrrrr

5x - y = 2 > 5y - x = 2
5y = 2 + x > y = 2/5 + x/5
INVERSE IS : f^-1 (x) = 2/5 + x/5

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