Răspuns:
Explicație pas cu pas:
<DAM = <DAB - <MAB = 90° - 60° = 30°
<DSA = 180° - <ADS - <DAM = 180° - 90° - 30° = 60°
<MST = < DSA = 60°
<M = 60°
<MTS = 180° - <M - < MST = 180° - 60° - 60° = 60°
∡DAM = ∡DAB - ∡MAB => ∡DAM = 90° - 60° => ∡DAM 30°
∡DSA = 180° - ∡ADS - ∡DAM => ∡DSA = 180° - 90° - 30° => ∡DSA = 60°
∡MST = ∡DSA = 60°
∡M = 60°
∡MTS = 180° - ∡SMT - ∡MST => ∡MTS = 180° - 60° - 60° => ∡MTS = 60°
