[tex]a=2,5= \frac{25}{10}= \frac{5}{2} \\ \\
b=- \frac{6}{5} \\ \\
a+b= \frac{25}{10}+(^{2)}- \frac{6}{5}) \\ \\
a+b= \frac{25}{10}- \frac{12}{10} \\ \\
\boxed{a+b= \frac{13}{10}} \\ \\
a*b= \frac{5}{2}*(- \frac{6}{5}) \\ \\
a*b=- \frac{30}{10} \\ \\
\boxed{a*b=-3} [/tex]
