Answer
$-4$
Work Step by Step
Evaluate applying the order of operations.
$(6-9)(8-12)\displaystyle \div\frac{5^{2}+4\div 2}{8^{2}-9^{2}+8}=\qquad$... Parentheses first,
$=(-3)(-4)\displaystyle \div\frac{5^{2}+4\div 2}{8^{2}-9^{2}+8}$
$=12\displaystyle \div\frac{5^{2}+4\div 2}{8^{2}-9^{2}+8}=\qquad$... Exponents
$=12\displaystyle \div\frac{25+4\div 2}{64-81+8}\qquad$...$\left\{\begin{array}{ll}
numerator: & division\\
denominator: & left\ to\ right... subtract
\end{array}\right.$
$=12\displaystyle \div\frac{25+2}{-17+8}\qquad$...$\left\{\begin{array}{ll}
numerator: & add\\
denominator: & add
\end{array}\right.$
$=12\displaystyle \div\frac{27}{-9}\qquad$... reduce the fraction by 9
$=12\div(-3)\qquad$... an odd number of minus signs...
=$-4$
