Hi there!
8.
Recall the following properties:
[tex]\frac{1}{x^{-a}} = x^a\\\\x^0 = 1[/tex]
Thus, we can rearrange the expression in parts.
[tex](3x)^0 = 1\\\\x^4 = x^4\\\\y^{-4} = \frac{1}{y^4}\\\\\frac{1}{x^{-3}} = x^3\\\\\frac{1}{y^{-7}} = y^7[/tex]
Now, combine these terms:
[tex](1) * x^4 * \frac{1}{y^4} * x^3 * y^7 = \frac{x^4 * x^3 * y^7}{y^4}[/tex]
More properties:
[tex]x^a * x^b = x^{a + b}\\\\\frac{x^a}{x^b} = x^{a - b}[/tex]
Rewrite:
[tex](1) = x^{4 + 3} * y^{7 - 4} = \boxed{\text{D) } x^7y^3}[/tex]
9)
Begin by solving the inside of the parenthesis.
[tex](3^2 + 3^0)^2 = (9 + 1)^2 = 10^2 = 100\\\\(6^{-2} + 3)^0 = 1\\\\100 - 1 = \boxed{ \text{ B. 99}}[/tex]
10)
Simplify the inside of the parenthesis using the above properties.
[tex](\frac{x^2y^5z^3}{xy^7})^{-2} = (\frac{xz^3}{y^2})^{-2}[/tex]
Since there is a negative in the outside exponent, we must take the reciprocal. (flip the numerator and denominator).
[tex]=( \frac{y^2}{xz^3})^2[/tex]
Square both the numerator and denominator.
Recall the property:
[tex](x^a)^b = x^{ab}[/tex]
[tex]= \frac{y^{2*2}}{x^2 * z^{3 * 2}} = \boxed{ \text{C. }\frac{y^4}{x^2z^6}}[/tex]
