Răspuns:
[tex]7 \frac{1}{5} = \frac{7 \times 5 + 1}{5} = \frac{36}{5} [/tex]
perimetrul=4L
l
[tex] \frac{36}{5} = 4l[/tex]
[tex]l = \frac{ \frac{36}{5} }{4} [/tex]
[tex]l = \frac{36}{5} \times \frac{1}{4} [/tex]
[tex]l = \frac{9}{5} [/tex]
Aria=l²
[tex]aria = ( \frac{9}{5} ) {}^{2} [/tex]
[tex]aria = \frac{81}{25} [/tex]
