Question

log3(x+3)+log3(x-4)=3

Answer 1

log3 (x + 3) + log3 (x - 4) = 3
log3 [(x + 3)(x - 4)] = 3
(x + 3)(x - 4) = 3³
x² - x - 12 = 9
x² - x - 21 = 0

Soma e Produto

x1 + x2 = - b/a
x1 + x2 = 1

x1 . x2 = c/a
x1 . x2 = - 21