tolong dijawab yh ku kasih poin besar kok

p x l = 392
(3x+4)(x+6) = 392
3x² + 18x + 4x + 24 = 392
3x² + 22x = 368
3x² + 22x - 368 = 0
(x - 8)(3x + 46) = 0
x = 8 atau x = -46/3

Ambil nilai x positif, maka:
p = 3(8) + 4 = 28 cm
l = 8 + 6 = 14 cm