Simplifying (x + 3/x - 1) + (4/1 - x) to a Constant: Easy Algebra Help

[Joza]

Easy algebra help!

Show that (x + 3/x - 1) + (4/ 1 - x) simplifies to a constant.


The answer is 3, but all I can get is 1. It's wracking my brain. ANYONE?

 

[christianjb]

Show that (x + 3/x - 1) + (4/ 1 - x) simplifies to a constant.


The answer is 3, but all I can get is 1. It's wracking my brain. ANYONE?

Do you mean (x+3)/(x-1)+4/(1-x) ? Put in the correct brackets.

 

[Joza]

Yes! Sorry I messed up my notation...

 

[christianjb]

x-1 = -(1-x)
so (x+3)/(x-1)+4/(1-x)=(x+3)/(x-1)-4/(x-1)
denominators are equal- so can add numerator
=(x-1)/(x-1)=1

So I get the same answer.

 

[Joza]

?

The answer book says 3.

 

[denverdoc]

book is wrong.

(x+3)/(x-1)=-4/(1-x)=4/(x-1) putting 3 in for x,
6/2=4/2 ? is right.

 

[Gib Z]

Yup Book is definitely wrong. Its 1. The question was show that it simplifies to a constant, so either way its alrite.

 

[danago]

For a question like this, you can easily check it with a calculator. Just pick any random value of x, and evaluate.