Jawabanmu

2014-06-05T16:28:53+07:00
Lp = 2 (pl + pt + lt)
1300 = 2 (20.15 + 20t + 15t)
1300 = 600 + 40t + 30t
1300 = 600 + 70t
1300 - 600 = 70t
700 = 70t
700/70 = t
10 = t

jadi tinggi balok tsb adalah 10cm
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