Question

Solve the following logarithmic equations.
log(x) + log(x − 1) = log(3x + 12)

Answer 1

The answer to your question is: x = 6

Explanation:

Data

log(x) + log(x − 1) = log(3x + 12)

log x(x - 1) - log(3x + 12) = 0

log x(x - 1) / (3x + 12) = 0

Antilog x(x - 1) /(3x + 12) = 1

x² - x = 3x + 12

x² - x - 3x - 12 = 0

x² - 4x - 12 = 0

(x - 6) (x + 2) = 0

x1 = 6 x2 = -2

x2 is negative, but there are no negative logs, so -2 is not an answer to this equation.