Răspuns :
Răspuns:
a) A=10×6/2=60/2=30 cm^2
b) A=8×7=56 cm^2
c) l=20:4=5---->A=5^2=25 cm^2
Explicație pas cu pas:
a)
[tex] \frac{c1 \times c2}{2} = \frac{10 \: cm \times 6 \: cm}{2} = \frac{60 \: cm}{2} = 30 \: cm[/tex]
b)
[tex]lungime \times latime = 8 \times 7 = 56 \: cm[/tex]
c)
[tex]p = 4 \times l = 20 \\ 4 \times l = 20 \\ 20 \div 4 = 5 \\ a = l ^{2} = 5 ^{2} = 25 \: cm[/tex]