Respuesta :

Recall the following property of exponents:

[tex]a^{-n}=\frac{1}{a^n}[/tex]

Then:

[tex]4^{-2}\cdot7^{-2}=\frac{1}{4^2}\cdot\frac{1}{7^2}=\frac{1}{16}\cdot\frac{1}{49}=\frac{1}{784}[/tex]