Respuesta :
Explicación paso a paso:
Perímetro
A+B+C
12cm+12cm+12cm=36cm
P=36cm
Semiperimetro
[tex]s = \frac{p}{2} \\ s = \frac{36}{2} \\ s = 18 \\ [/tex]
[tex]a = \sqrt{s(s - a)(s - b)(s - c)} \\ a = \sqrt{18(18 - 12)(18 - 12)(18 - 12)} \\ a = \sqrt{18(6)(6)(6)} \\ a = \sqrt{3888} \\ a = 62.35[/tex]