Jawabanmu

2014-05-18T21:26:41+07:00
Lp = 2(p×l + p×t + l×t)
Lp = 2((2a+3)×4a + (2a+3)×(2a-2) + 4a×(2a-2)
Lp = 2((8a²+12a) + (4a² +2a -6) + (8a² - 8a)
Lp = 2(8a² + 4a² + 8a² +12a + 2a - 8a - 6)
Lp = 2(20a² + 6a - 6)
Lp = 40a² + 12a - 12 cm²

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