<|system|>
If $\det \mathbf{A} = -1,$ then find $\det (\mathbf{7A}).$</s>.
<|user|>
Can you answer based on context?
<|assistant|>
In general, $\det (k \mathbf{A}) = k^2 \det \mathbf{A}.$ Thus,
\[\det (7 \mathbf{A}) = 7^2 (-1) = -49.\]