3log (3x - 1) + 3log ( x + 5) = 3 log 7

LogAritMa

³log (3x - 1) + ³log (x + 5) = ³log 7
³log (3x - 1)(x + 5) = ³log 7
(3x - 1)(x + 5) = 7
3x² + 14x - 12 = 0

Rumus abc
x1.2 = (-b ± √(b² - 4ac))/2a
x1.2 = (-14 ± √340)/6
x1.2 = (-14 ± 2√85)/6

Nilai x yg memenuhi :
(-7 + √85)/3