Evaluate: (-12y^2-6y-9)/(-3)

Expression: ${\left( -4{y}^{-2} \right)}^{3}$

Express with a positive exponent using ${a}^{-n}=\frac{ 1 }{ {a}^{n} }$

${\left( -4 \times \frac{ 1 }{ {y}^{2} } \right)}^{3}$

Calculate the product

${\left( -\frac{ 4 }{ {y}^{2} } \right)}^{3}$

To raise a fraction to a power, raise the numerator and denominator to that power

$-\frac{ 64 }{ {y}^{6} }$