Explicatii.
Un trapez isoscel cu diagonalele perpendiculare
se numeste trapez ortodiagonal.
Intr-un trapez ortodiagonal linia mijlocie = inaltimea.
.
[tex]\displaystyle\bf\\Aria~trapezului~=~\frac{(B+b)\times h}{2}=\frac{(B+b)}{2}\times h\\\\(B+b)~este~"baza mare + baza mica".\\\\\frac{(B+b)}{2}=Lm~(linia~mijlocie)\\\\Lm=h~deoarece~este~trapez~ortodiagonal.\\\\\implies~\frac{(B+b)}{2}=h=6~cm\\\\Aria=\frac{(B+b)\times h}{2}=\frac{(B+b)}{2}\times h=h\times h=6\times6=\boxed{\bf36~cm^2}[/tex]
