Question

Срочноооооо!!!!!!!!!!

Answer 1

$5.4 - 9 + ( - 2.51x) = 18 + 5.4 - 2.71x \\ - 9 - 2.51x = 18 - 2.71x \\ - 2.51x + 2.71x = 18 + 9 \\ 0.2x = 27 \\ x = 135$