Question

log7(5x-9)>=log7 4x​

Answer 1

$log_{7} (5x-9)\geq log_{7} (4x)$

ОДЗ:

$\left \{ {{5x-9\geq 0} \atop {4x\geq 0}} \right.$     $\left \{ {{x\geq 1.8} \atop {x\geq 0}} \right.$     x ∈ [1.8;  +oo).

$5x-9 \geq 4x\\5x-4x \geq 9\\1x \geq 9 = > Otvet: [9;+oo).$