SinA = tgA/√(1+tg²a)=(4/3)/√(1+(4/3)²)=(4/3)/√(1+16/9)=(4/3)/√(25/9)=(4/3)/(5/3)=4/5=0.8
SinA=BC/AB ⇒ BC=AB*SinA=5*0.8=4
SinA = tgA/√(1+tg²a)=(4/3)/√(1+(4/3)²)=(4/3)/√(1+16/9)=(4/3)/√(25/9)=(4/3)/(5/3)=4/5=0.8
SinA=BC/AB ⇒ BC=AB*SinA=5*0.8=4