EDGE Math 8

Simplify each expression. Assume that the variables represent nonzero real numbers. Then choose your answer.

1.	${(a^{3} b^{- 2} c^{0})}^{- 3}$

\frac{b^{6}}{a^{9}}

\frac{a^{9}}{b^{6}}

a^{9} b^{6}

none of the choices

Answer: $\frac{b^{6}}{a^{9}}$

2.	${(2 s^{- 3} t^{4})}^{3}$

\frac{8 t^{7}}{s^{6}}

\frac{6 t^{7}}{s^{6}}

\frac{8 t^{12}}{s^{9}}

none of the choices

Answer: $\frac{8 t^{12}}{s^{9}}$

3.	${(5 t)}^{2} {(3 t^{2})}^{2}$

225 t^{6}

15 t^{12}

60 t^{6}

none of the choices

Answer: $225 t^{6}$

4.	$(6 x^{2} y^{- 2}) (- 2 y^{3} z)$

12 x^{2} y^{6} z

\frac{- 12 x^{2} z}{y}

\frac{- 12 x^{2} z}{y^{6}}

none of the choices

Answer: none of the choices; the answer is $- 12 x^{2} y z$ .

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