[tex]\displaystyle A~se~vedea~figura~de~mai~jos. \\ \\ Avem~e= \frac{a+b}{2},~f= \frac{b+c}{2},~g= \frac{c+d}{2},~h= \frac{d+a}{2}. \\ \\ Asadar~e+f+g+h=a+b+c+d. \\ \\ Prin~urmare~a+b+c+d+e+f+g+h=2(a+b+c+d)=par. \\ \\ Dar~numerele~noastre~au~suma~impara!~Deci~H~nu~este~geometrica. \\ \\ b)~Il~inlocuim~pe~8~cu~11~si~punem~numerele~ca~in~imagine.[/tex]
