Answer :

Answer:

  A)  x = 4, -1

Step-by-step explanation:

You want the solutions to the rational equation ...

  [tex]\dfrac{x}{2}=\dfrac{3x+4}{2x}[/tex]

Trial and error

We can rearrange this equation to make it easy to try the different answer choices.

  [tex]\dfrac{x}{2}=\dfrac{3x}{2x}+\dfrac{4}{2x}=\dfrac{3}{2}+\dfrac{2}{x}\\\\\\x=3+\dfrac{4}{x}\qquad\text{multiply by 2}[/tex]

Trying the first answer choice, we have ...

  4 = 3 +4/4 . . . . true

  -1 = 3 +4/(-1) . . . . true

The values of answer choice A satisfy the equation.

Quadratic

Multiplying the equation by 2x gives ...

  x² = 3x +4

  x² -3x -4 = 0 . . . . put in standard form

  (x -4)(x +1) = 0 . . . . factor

  x = 4, -1 . . . . . . . . . values that make the factors zero

The solutions are x = 4, -1, matching choice A.

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Additional comment

Subtracting the right-side expression gives an equation of the form f(x)=0. That is, the solutions will be the x-intercepts of the graph of f(x). The attachment shows these solutions. In general, a graphing calculator can find solutions to problems like this pretty easily.

View image sqdancefan

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