-4 1/2 + (-2 1/3)
[tex]-4 \frac{1}{2} + (-2 \frac{1}{3} )[/tex]

[tex]-4\frac12+(-2\frac13)=-4\frac12-2\frac13=-4\frac36-2\frac26=-(4\frac36+2\frac26)=-6\frac56\\\\\\5\frac25-6\frac57=5\frac{2\cdot7}{5\cdot7}-6\frac{5\cdot5}{7\cdot5}=5\frac{14}{35}-6\frac{25}{35}=-(6\frac{25}{35}-5\frac{14}{35})=-1\frac{11}{35}[/tex]