Răspuns:
Explicație pas cu pas:
2/3 - 4/5 = 10/15 - 12/15 = -2/15
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3/7 - 4/14 = 3/7 - 2/7 = 1/7
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3/15 - 1/15 + 2/3 = 2/15 + 10/15 = 12/15 = 4/3
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2. A = 45 ore 28 minute
compl. A = ?
supl A = ?
unghiul se masoara in grade, nu in ore
A = 45°28'
compl. A = 90° - 45°28' = 89°60' - 45°28'' = 44°32''
supl A = 180° - 45°28'' = 179°60'' - 45°28'' = 134°32''