EDGE Math 8

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

1.	$\frac{t^{2} - 1}{6 (t^{2} - 5 t + 4)} \div \frac{t^{2} - 6 t + 5}{2 t - 2}$

\frac{t + 1}{3 t^{2} - 27 t + 60}

\frac{t + 1}{t^{2} - 9 t + 20}

\frac{1}{t - 20}

none of the choices

Answer: $\frac{t + 1}{3 t^{2} - 27 t + 60}$

2.	$\frac{5 x - 20}{5 x + 30} \div \frac{10 (x^{2} - 16)}{x^{2} + 5 x - 6}$

\frac{x - 1}{10 x + 40}

\frac{x - 1}{x + 4}

\frac{x - 1}{5 x + 20}

none of the choices

Answer: $\frac{x - 1}{10 x + 40}$

3.	$\frac{3 x - 27}{6 x + 54} \div \frac{x^{2} - 10 x + 9}{x^{2} - 81}$

\frac{x - 9}{x - 1}

\frac{x - 9}{2 x - 1}

\frac{x - 9}{2 x - 2}

none of the choices

Answer: $\frac{x - 9}{2 x - 2}$

4.	$\frac{t^{3} - 1}{t^{2} - 1} \div \frac{t^{3} (t - 1)}{t {(t + 1)}^{2}}$

\frac{t^{3} + 2 t^{2} + 2 t + 1}{t - 1}

\frac{t^{3} + 2 t^{2} + 2 t + 1}{t^{3} - t^{2}}

\frac{t^{3} + 2 t^{2} + 2 t + 1}{t^{2} - t}

none of the choices

Answer: $\frac{t^{3} + 2 t^{2} + 2 t + 1}{t^{3} - t^{2}}$

5.	$\frac{m^{3} - 8}{25 (m^{2} - 4)} \div \frac{(m + 2) (m - 2)}{m^{2} - 4 m + 4}$

\frac{m^{3} - 8}{25 m^{2} + 100 m + 100}

\frac{m - 2}{25}

\frac{m^{2} - 4}{25}

none of the choices

Answer: $\frac{m^{3} - 8}{25 m^{2} + 100 m + 100}$

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