What values for x must be excluded in the following fraction? x-3/(4x-5)(x+1)?

Question

Could someone please walk me through this?

Answer 1

We don't want the denominator of the fraction to equal zero, or otherwise it would be undefined.

You can set each binomial in the denominator equal to zero, and solve for "x". But the answer means that x cannot equal that value!

(4x-5) = 0
4x = 5
x = 5/4
x ≠ 5/4

(x+1) = 0
x = -1
x ≠ -1

So both "-1" and "5/4" must be excluded, or are domain restrictions.

Answer 2

Well if you divide by zero you'll get a non sensical answer (it isn't always infinity). So you'll have to stop the denominator from being 0.
This will happen when (4x-5) = 0 or (x+1)=0. (If one is 0 then 0 times anything is still zero).
So for values where 4x = 5 (x= 5/4) or x = -1.

Answer 3

Is that the same as x - (3(x-1)/(4x-5)) ?
If so then x=1.25 gives division by zero - is that what you mean?

Answer 4

It cannot be -1 or +1.25
This is to avoid division by zero.
IT can be everything else.

Answer 5

x can't be = -1,(5/4)

Answer 6

duh x=5/4 and x=-1...friggin idiot