Răspuns :
Răspuns:
Explicație pas cu pas:
a) numitorul comun 12
[tex]\frac{-3}{4} + \frac{5}{6} = \frac{-9+10}{12}=\frac{1}{12}[/tex]
b)
numitorul comun 8
[tex]\frac{5}{8} -2=\frac{5-16}{8} = \frac{-11}{8}[/tex]
c)
[tex]\frac{-3}{10} * \frac{-15}{9}= \frac{45}{90} = \frac{1}{2}[/tex]
simplificam ( impartim cu 45 sus si jos )
d)
[tex]\frac{28}{12} -\frac{35}{15} = \frac{28*15-35*12}{12*15} =\frac{420-420}{180} = \frac{0}{180} = 0[/tex]
e)
[tex]\frac{2}{3} : ( - 12 ) =\frac{2}{3} * \frac{1}{-12} = \frac{2}{-36} = \frac{1}{-18 } = - \frac{1}{18}[/tex]
f)[tex]\frac{-5}{3}+1=\frac{-5+3}{3}=\frac{-2}{3}=-\frac{2}{3}[/tex]
a) [tex]-\frac{3}{4} + \frac{5}{6} =[/tex]
[tex]-\frac{3*3}{3*4} + \frac{2*5}{2*6}=[/tex]
[tex]-\frac{9}{12} + \frac{10}{12} = \frac{1}{12}[/tex]
b) [tex]\frac{5}{8} - 2 =[/tex]
[tex]\frac{5}{8} - \frac{2}{1} =[/tex]
[tex]\frac{5}{8} - \frac{2*8}{1*8} =[/tex]
[tex]\frac{5}{8} - \frac{16}{8} = -\frac{11}{8}[/tex]
c) [tex]-\frac{3}{10} * (-\frac{15}{9}) =[/tex]
[tex]\frac{45}{90} = \frac{9}{18} = \frac{1}{2}[/tex]
d) [tex]\frac{28}{12} - \frac{35}{15}[/tex]
[tex]\frac{28*15}{12*15} - \frac{35*12}{12*15} =[/tex]
[tex]\frac{420}{180} - \frac{420}{180} =[/tex]
[tex]\frac{0}{180} = 0[/tex]
e) [tex]\frac{2}{3} : (-12) =[/tex]
[tex]\frac{2}{3} : (-\frac{12}{1}) =[/tex]
[tex]\frac{2}{3} * (-\frac{1}{12}) =[/tex]
[tex]-\frac{2}{36} = -\frac{1}{18}[/tex]
f) [tex]-\frac{5}{3} + 1 =[/tex]
[tex]-\frac{5}{3} + \frac{1}{1} =[/tex]
[tex]-\frac{5}{3} + \frac{1*3}{1*3} =[/tex]
[tex]-\frac{5}{3} + \frac{3}{3} = -\frac{2}{3}[/tex]
