Jawabanmu

2014-03-28T21:25:43+07:00
L = 38 - x
p = 5 + l = 5 + 38 - x = 43 - x

luas = p x l = (38 - x) (43 - x)
       = 1634 - 38x - 43x + x²
       = 1634 - 82x + x²
2014-03-28T23:55:42+07:00
L = 38 - x
p = 5 + l = 5 + 38 -x
             = 43 - x
luas = p . l
       = (43 - x)(38 - x)
       =(43 . 38) +(43 . -x) - (x . 38) (-x . -x)
       = 1634 - 43x - 38x +x²
       = 1634 - 81x + x²

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