a)
[tex]( - \frac{15}{23} ) + ( - \frac{19}{23} ) = \frac{ - 15 - 19}{23} = - \frac{34}{23} [/tex]
b)
[tex]( \frac{3}{4} + \frac{5}{3} ) + (7 + \frac{1}{5} ) = ( \frac{9 + 20}{12}) + ( \frac{35 + 1}{5} ) = \frac{29}{12} + \frac{36}{5} = \frac{145 + 432}{60} = \frac{577}{60} [/tex]
aho estan paso a paso :)
