Question

Triunghiul ABC -tr. isoscel, AB=AC=(x+3),BC=18cm, AD_|_BC ,AD=X. Aflati: a) x=?
b)Perimetrul tr.

Answer 1

in triunghiul ADB, m< D=90, AB=x+3, DB=9, AD=X aplici Th lui Pitagora 
$(x+3)^{2} = x^{2} +81$$x^{2} +6x+9= x^{2} +81$$6x=72$$x=12$$P=AB+AC+BC=2*(12+3)+18=30+18=48$