Question

Șapte plăcute identice de gresie sub forma de patrat alcatuiesc un dreptunghi cu perimetrul de 320cm
Ce lungime are latura unei plăcuțe.

Answer 1

   
[tex]\displaystyle\\ \text{7 este numar prim.}\\ \text{Rezulta ca placutele sunt asezate pe un singur rand, astfel:}\\\\ \boxed{\texttt{\Big ~P1~}}\boxed{\texttt{\Big ~P2~}}\boxed{\texttt{\Big ~P3~}}\boxed{\texttt{\Big ~P4~}}\boxed{\texttt{\Big ~P5~}}\boxed{\texttt{\Big ~P6~}}\boxed{\texttt{\Big ~P7~}}\\\\ x= \text{Latura unei placute }\\\\ P=2(7x+x)= 2\cdot 8x = 16x\\\\ P=320~cm\\\\ 16x=320\\\\ x= \frac{320}{16} \\\\ \boxed{\bf x=20~cm}[/tex]