Jawabanmu

2014-05-09T06:29:30+07:00
S = 1/2 k
  = 1/2*(5+7+8)
  = 10
rl = (a*b*c)/(4*√s(s-a)(s-b)(s-c))
   = (5*7*8)/(4*√10(10-5)(10-7)(10-8))
   = 280/(4*√10*5*3*2)
   = 280/4*√300
   = 280/4*17,3
   = 280/69,2
   = 4,05

semoga membantu!!!!!!!!!!
2014-05-09T06:58:54+07:00
Rl = a*b*c/ 4*L segitiga
   = 5*7*8/ 4*17,5
   = 280/70
   = 4
Semoga membantu, maaf kalo ada yang salah....

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