[tex]1)( \frac{3}{8} + \frac{5}{12} ):1 \frac{7}{12} =\\
=( \frac{9}{24} + \frac{10}{24} ):\frac{19}{12}=\\
= \frac{19}{24} :\frac{19}{12}=\\
= \frac{19}{24} \cdot \frac{12}{19}= \frac{1}{2}
[/tex]
[tex]2) \overline{7a3}\vdots 3=>a\in\{2,5,8\}=>723,753,783[/tex]
[tex]3) \frac{2x-4}{0,5} =12\\
2x-4=0,5\cdot 12\\
2x-4=6\\
2x=10\\
x=5[/tex]
4)AC=AB+BC=24
AD=DC=24:2=12
BD=BC-DC=15-12=3
5)Daca intr-un triunghi dreptunghic lungimea unei catete este
jumatate din lungimea ipotenuzei , atunci masura unghiului care se opune
acelei catete este 30 grade.