3. a) p-perimetrul
[tex]p = ab + bc + cd + de + ef + fg + gh + hi + ij + ja \\ p = 1 + 2.5 + 1.5 + 2 + 2.5 + 1 + 2.5 + 1 \: cm [/tex]
b) Aici vei imparti figura astfel (cum am facut in imagine)
[tex]a = 1.5 \times 2 + 1 \times 9 + 0.5 \times 5 cm[/tex]4.
[tex]10 \frac{1}{2} = \frac{10 \times 2 + 1}{2} [/tex]
4.a)
[tex]a = 6.4 \times \frac{10 \times 2 + 1}{2} = \frac{6.4 \times 21}{2} = 3.2 \times 21 = 67.2 \: cm {}^{2} [/tex]
b)
[tex]a2 = 67.2 \div 4 = 16.8 \: cm {}^{2} [/tex]
[tex]16.8 = 10.5 \times x \\ x = 16.8 \div 10.5 = 1.6 \: cm[/tex]
[tex]l - x = 6.4 - 1.6 = 4.8cm[/tex]
c)(fig.2)
[tex]a = 67.2 \times 2 + 20 \times 10.5 \times 2 + 20 \times 6.4 \times 2 = 810.4 \: cm {}^{2} [/tex]
[tex]v = l \times latime \times h = 10.5 \times 6.4 \times 20 = 1.344cm {}^{3} [/tex]
Exercitiul 2 zic eu ca il faci si singur :))))
daca nu e corect imi pare rau, am dat tot ce am avut mai bun din mine )
