Jawabanmu

2014-05-05T15:08:13+07:00
2(3X-1 + 2X+3) = 54
6X-2+4X+6       = 54
10X+4              = 54
10X                 = 50
X                     = 5

panjang salah satu sisi >> (2X+3) >> 2*5+3 = 10+3 = 13 
Jawaban paling cerdas!
2014-05-05T15:08:28+07:00
Keliling jajar genjang = sisi + sisi + sisi + sisi
-> 54 = 2x + 3 + 2x + 3 + 3x -1 + 3x - 1
-> 54 - 3 - 3 + 1 + 1 = 2x + 2x + 3x +3x
-> 50 = 10x
-> x = 5
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panjang sisi 1 -> 2x + 3 = 2(5) + 3 = 10 + 3 = 13cm
panjang sisi 2 -> 3x - 1 = 3(5) - 1 = 15 - 1 = 14 cm