How do you solve #-3/(x+1)=4/(x-1)#?

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Answer 1 · 2017-05-02T09:09:24

Multiply each side by the denominators and simplify.

#-3 / color(red)(x+1) = 4/color(blue)(x-1)#

First off, multiply both sides by the denominators.

#-color(blue)(3(x-1))/color(red)(x+1) = 4#

#-color(blue)(3(x-1))= color(red)(4(x+1)#

Then, expand the brackets.

#color(blue)(-3x+3) = color(red)(4x + 4)#

Rearrange the equation.

# -3x - 4x = 4 - 3#

              #x=-1/7#

Double check your answer by substituting #x=-1/7# back into the original equation.

#-3 / color(red)(-1/7+1) = 4/color(blue)(-1/7-1)#

#color(red)(-3.5 = color(blue)(-3.5)#

Therefore, your answer #x=-3.5# is correct.