fie AH_|_BC, =>triunghiul ABH dreptuinghic in H, => AH =1/2din AB=28/2=14cm(cateta opusa unghi de 30 grade e jumatate din ipotenuza)
aria ABC=(BCxAH)/2=(36x14)/2=252cm^2
Fie CP_|_AB =>d(C, AB)=CP
dar aria ABC=ABxCP=252cm^2 =>252=CPX28 =>CP=252:28=9cm.