Question

Calculati: a) (-7/12+3/8)*(-8/15)+(-7/24)*(+16/21) ; b) (-8/15+3/10):(-14/15)+(-2/9+1/12):(-5/9)

Answer 1

a) amplificam prima paranteza cu 2 si 3

$( \frac{ - 14}{24} + \frac{9}{24} ) \times \frac{ - 8}{15} + \frac{ - 7}{24} \times \frac{16}{21} \\ \\ \ \frac{ - 5}{24} \times \frac{ - 8}{15} + \frac{ - 2}{9} \\ \\ \\ \frac{1}{9 } + \frac{ - 2}{9} = \frac{ - 1}{9}$

b)

$( \frac{ - 16}{30} + \frac{ 9}{30} ) \div \frac{ - 14}{15} + (\frac{ - 8}{36} + \frac{3}{36} ) \div \frac{ - 5}{9} \\ \\ \frac{ - 7}{30} \div \frac{ - 14}{15} + \frac{ - 5}{36} \div \frac{ - 5}{9} \\ \\ \frac{ - 7}{30} + \frac{15}{ - 14} + \frac{ - 5}{36} \times \frac{9}{ - 5} \\ \\ \frac{ - 1}{ - 4} + \frac{ - 1}{ - 4} = \frac{ - 2}{4}$

Answer 2

Sper ca înțelegi ce am scris și ca te-am ajutat