Algebra: solve 3/4 =1-3x-2 / x + 1 algebraically

Missy

New member
Joined
Jan 16, 2008
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Can you help me with this I think that it is a rational function
3/4=1-3x-2
x+1
can you explain the steps that I need to take to solve this problem?
 
Re: Algebra

What you are asking is unclear. Please indicate what the instructions are for this problem. Please copy it exactly as it appears on your problem sheet, with the instructions.
 
Re: Algebra

the instructions are to solve the equation algebraically
and the problem is 3/4 =1-3x-2 / x + 1
Being out of school for some thirty years I need all the help I can with Alegebra :cry:
 
Re: Algebra

Missy said:
the instructions are to solve the equation algebraically
and the problem is 3/4 =1-3x-2 / x + 1
Being out of school for some thirty years I need all the help I can with Alegebra :cry:

Does your problem look as follows (somewhat):

\(\displaystyle solve \, algebraically:\)

\(\displaystyle \frac{3}{4}\, = \, \frac {1\, - \, 3x \, - \, 2}{x\, + \, 1}\)

If it does:

Since both sides contain fractions, my preference (strictly preference - not a rule) - is to get rid of the fraction by multiplying with the LCD (considering all the denominators from both sides of = sign)

In this case it is 4 * (x+1). So:

\(\displaystyle \frac{3}{4}\, = \, \frac {1\, - \, 3x \, - \, 2}{x\, + \, 1}\)

\(\displaystyle 4\cdot ( x\, + \, 1) \cdot \frac{3}{4}\, = \, 4\cdot ( x\, + \, 1) \cdot \frac {-1\, - \, 3x }{x\, + \, 1}\)

After eliminating common factors

\(\displaystyle ( x\, + \, 1) \cdot 3\, = \, 4\cdot (-1\, - \, 3x)\)

Now simplify above by multiplying - isolate 'x' - and solve.
 
Re: Algebra

Missy said:
the instructions are to solve the equation algebraically
and the problem is 3/4 =1-3x-2 / x + 1
Being out of school for some thirty years I need all the help I can with Alegebra :cry:
You need to start using brackets, Missy; your equation should appear like this: 3/4 = (1-3x-2) / (x + 1)

Another way to solve is use cross-multiplication; RULE: if a/b = c/d, then ad = bc
So with yours:
3(x + 1) = 4(1 - 3x + 2)
3(x + 1) = 4(-3x - 1)
3x + 3 = -12x - 4
15x = -7
x = -7/15
OK??
 
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