[tex]\displaystyle\bf\\1)\\25-25:(2+3)=25-25:5=25-5=\boxed{\bf20}\\\\2)\\Patratele~perfecte~de~2~cifre~sunt: \\\{4^2;~5^2;~6^2;~7^2;~8^2;~9^2\}=\{16;~25;~36;~49;~64;~81\}\\Avem~un~numar~de~\boxed{\bf6}~patrate~perfecte~cu~2~cifre\\\\3)\\A\cap B=\O~~(multimea~vida)\\\\4)\\L_{cerc}=\pi D\implies D=\frac{L_{cerc}}{\pi}=\frac{20\pi}{\pi}=\boxed{\bf20~cm}[/tex]
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[tex]\displaystyle\bf\\5)\\Dreptunghiul~ACC'A'~are:\\Inalinea h = AA'=CC'=3~cm~si baza b=AC=A'C'=3\sqrt2~cm\\deoarece~sunt~diagonale.\\Aria=h\times b=3\times 3\sqrt2=\boxed{\bf9\sqrt2~cm^2}\\\\6)\\\textbf{Numarul elevilor care au pbtinut }\\\textbf{cel putin media 6 si cel mult media 9 sunt:}\\\boxed{\bf~n=6+7+5+4=22~de~elevi}[/tex]
