EDGE Math 8

Perform the indicated operations and simplify the resulting expression. Choose the correct answer.

1.	$\frac{5}{6 x} + \frac{3}{2 x}$

\frac{8}{3 x}

\frac{7}{3 x}

\frac{7}{3}

none of the choices

Answer: $\frac{7}{3 x}$

2.	$\frac{7}{2 x^{2}} - \frac{2}{5 x^{3}}$

\frac{31}{10 x^{3}}

\frac{35 x - 4}{10 x^{3}}

\frac{7 x - 4}{2 x^{3}}

none of the choices

Answer: $\frac{35 x - 4}{10 x^{3}}$

3.	$\frac{4}{x + 5} - \frac{1}{x + 3}$

\frac{3 x + 7}{(x + 5) (x + 3)}

\frac{3 x - 7}{(x + 5) (x + 3)}

\frac{7 x - 3}{(x + 5) (x + 3)}

none of the choices

Answer: $\frac{3 x + 7}{(x + 5) (x + 3)}$

4.	$\frac{- 18}{x^{2} - 9} + \frac{x}{x + 3}$

\frac{x^{2} - 3 x - 18}{x^{2} - 9}

\frac{x - 6}{x - 3}

\frac{x^{2} - 3 x + 18}{x^{2} - 9}

none of the choices

Answer: $\frac{x - 6}{x - 3}$

5.	$\frac{5}{x + 2} - \frac{x + 2}{{(x + 2)}^{2}}$

\frac{4}{x + 2}

\frac{4 x}{x + 2}

\frac{4 x - 2}{x + 2}

none of the choices

Answer: $\frac{4}{x + 2}$

6.	$\frac{4}{x + 1} + \frac{4}{x - 1}$

\frac{8 x - 4}{(x + 1) (x - 1)}

\frac{8 x}{(x + 1) (x - 1)}

\frac{8 x}{x + 1}

none of the choices

Answer: $\frac{8 x}{(x + 1) (x - 1)}$

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