Question

6-{4+[-7-(-3-9+10)]}

Answer 1

6-{4+[-7-(-3-9+10)]}
6-{4+[-7-(-2)]}
6-{4+[-7+2]}
6-{4-5}
6+1=7

Answer 2

6-{4+[-7-(-3-9+10)]} =

6-{4+[-7-(-2)]} =

6-{4+[-7+2]} =

6-{4-5} =

6+1

=7

Espero ter ajudado. :))