Răspuns:
a)
compl: 90°-71°45'=89°60'-71°45'=18°15'
supl: 180°-71°45'=179°60'-71°45'=108°15'
b)
compl: 90°-39°25'=89°60'-39°25'=50°35'
supl: 180°-39°25'=179°60'-39°25'=140°35'
Explicatie:
suma a 2 unghiuri complementare=90°
suma a 2 unghiuri suplementare=180°
