Explicație pas cu pas:
a)
[tex]Aria(ABC) = \frac{AB \times AC \times \sin(A)}{2} = \frac{14 \times 10 \times \sin(30) }{2} = 70 \times \frac{1}{2} = 35 \: cm^{2} [/tex]
b)
[tex]Aria(ABC) = \frac{AB \times BC \times \sin(B)}{2} = \frac{28 \times 21 \times \sin(45) }{2} = 294 \times \frac{ \sqrt{2} }{2} = 147 \sqrt{2} \: cm^{2} [/tex]
c)
[tex]Aria(ABC) = \frac{BC \times CA \times \sin(C)}{2} = \frac{12 \times 10 \times \sin(60) }{2} = 60 \times \frac{ \sqrt{3} }{2} = 30 \sqrt{3} \: cm^{2} [/tex]
