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a) mC = m(ACB) = m(AED) = 55 - ungh alt int
b) m(ADE) = m(ABC) = 75 - ungh alt int
m(BDE) = 180-m(ADE) = 180-75 = 105 - ungh supl
m(A) = 180-55-75 = 180-130 = 50 - suma ungh in tr
c) masura ungh format de bis unghiurilor B si C = 180-B/2-C/2 = 180-75/2-55/2 = 180-37.5-27.5 = 180-65 = 115
