Breuken verm. (reeks 2)

Vermenigvuldig de breuken

\(\frac{9}{-10} . \left(\frac{10}{-10}\right)\)

\(\frac{9}{-10} . \left(\frac{10}{-10}\right)\\=+\frac{9}{10}.\frac{1}{1}\\=+\frac{9.1}{10.1}\\=\frac{9}{10}\)