Panjang sisi ABC adlh 5cm,12cm,dan 13cm. TENTUKAN! a. Keliling ABC b. Luas ABC c. Panjang jari lingkaran luar segitiga Tolong dijawab dengan lengkap

a. K = s+s+s
= 5+12+13
= 30 cm
b. L = at/2
= 5.12/2
= 30 cm"
c. S = 1/2 (a+b+c)
= 1/2 (5+12+13)
= 1/2 (30)
= 15
L = _/s(s-a)(s-b)(s-c)
= _/15(15-5)(15-12)(15-13)
= _/15(10)(3)(2)
= _/900
= 30
r = abc/4L
= 5.12.13/4.30
= 780/120
= 13/2
= 6,5 cm