a)
[tex]3 \frac{5}{7} + x = 4[/tex]
[tex]x = 4 - 3 \frac{5}{7} [/tex]
[tex]x = \frac{2}{7} [/tex]
b)
[tex] \frac{5}{9} + y = 1[/tex]
[tex]y = 1 - \frac{5}{9} [/tex]
[tex]y = \frac{4}{9} [/tex]
c)
[tex]3 \frac{8}{10} + z = 5[/tex]
[tex]z = 5 - 3 \frac{8}{10} [/tex]
[tex]z = 1 \frac{2}{10} [/tex]
