Răspuns:
Explicație pas cu pas:
a)
G + D = 180°
G = 4D/5
4D/5 + D = 180°
4D/5 + 5D/5 = 180°
9D/5 = 180°
D = 180°*5/9 = 100°
G = 4*100°/5 = 80°
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b)
F + D = 180°
F + 5D/7 = 180°
7D/7 + 5D/7 = 180°
12D/7 = 180°
D = 7*180°/12 = 105°
F = 5*105°/7 = 75°
