Panjang jarilingkaran luar swgitiga yg panjang sisinya 15cm,17cm dan 8cm adalah

keliling = 15+17+8 = 40 cm
s = 40/2 = 20

Luas = √20(20-17)(20-15)(20-8)
= √20x3x5x12
= √4²x5²x3²
= 4x5x3 = 60 cm²

R = (15x17x8)/(4x60) = (8/4 x 15/60 x 17)
= (2/4 x 17)
= 34/4
= 8,5 cm