Răspuns:
1)
∡BMC = ∡DMC
BM = DM } => (LUL) => ΔMBC ≡ ΔMDC
MC = MC
2)
∡RPS = ∡TSP
∡RSP = ∡TPS } => (ULU) => ΔRPS ≡ ΔTSP => RP ≡ TS
PS = PS
3)
AE = AI => ΔAEI = isoscel
ΔAEI = isoscel
EU = UI } => AU = bisectoare ; perpendiculara =>
AU ⊥ EI => ∡AUE = ∡AUI = 90°
