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

1 Answer
May 2, 2017

Multiply each side by the denominators and simplify.

Explanation:

-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.