[tex]1.\,\,\,\text{Calculati perimetrul unui triunghi daca:}\\\\a)\,\,\,p = 5,7 \Rightarrow P = 2p \Rightarrow P = 2\cdot 5,7 \Rightarrow P = 11,4[/tex]
[tex]\\b)\,\,\,AB = 4\text{ cm};\,\,BC = \dfrac{3}{4}\cdot AB;\,\,AC = \dfrac{AB+BC}{2}\\\\ P = AB+AC+BC\\ \\= AB+\dfrac{AB+BC}{2}+\dfrac{3}{4}\cdot AB\\\\ = 4+\dfrac{4+\dfrac{3}{4}\cdot 4}{2}+\dfrac{3}{4}\cdot 4\\ \\ = 4+\dfrac{7}{2}+3=\dfrac{14+7}{2} =\dfrac{19}{2}\text{ cm}[/tex]
[tex]\\c)\,\,\,AB = 30\text{ mm};\,\,BC = 1,8\text{ cm};\,\,AC = 0,24\text{ dm}\\ \\ P = AB+BC+AC = 30\div 10 +1,8+0,24\cdot 10 =\\ = 3+1,8+2,4 = 7.2\text{ cm}\\\\[/tex]
L-am făcut doar pe 1. E prea mult.
