3/5×6/7+3/5×(-1/7)=..................

Răspuns :

[tex]\frac{3}{5}\cdot \frac{6}{7}+\frac{3}{5}\cdot \frac{-1}{7}=\\ \frac{3\cdot6}{5\cdot7}+\frac{3\cdot(-1)}{5\cdot7}=\\ \frac{18}{35}-\frac{3}{35}=\\ \frac{18-3}{35}=\\ \frac{15}{35}^{(5}=\frac{3}{7}\\ *^{(5}\text{ - simplificare cu 5}[/tex]
3/5×6/7+3/5×(-1/7)=. (+)×(-)=(-)
=18/35-3/35=
=15/35= (se simplifică cu "5")
=3/7