Bonjour.
A) Sinus(x)=opposé/hypothénuse
sinus(55°)= JL/KL
=sinus(55°)=5,6/KL
=5,6*1/sin(55°)
KL≃ 6,8
B) Cosinus(x)=adjacent/hypothénuse
cosinus(38°)=5,8/KL
=(5,8*1)/cos(38°)
KL
≃7,4cm
C) tangente(x)=opposé/adjacent
tan(42°)=9,3/KL
=9,3*1/tan(42°)*
KL≃10,3cm
Bonne journée.