=> x là bội chung của 4;5;8
\(B\left(4\right)\in\left\{0;\pm4;\pm8;\pm12;\pm16;\pm18;...\right\}\)
\(B\left(5\right)\in\left\{0;\pm5;\pm10;\pm15;\pm20;\pm25;\pm30;...\right\}\)
\(B\left(8\right)\in\left\{0;\pm8;\pm16;\pm24;\pm32;\pm40;\pm48;...\right\}\)
=> \(B\left(4,5,8\right)\in\left\{0;\pm40;\pm80;\pm120;\pm160;\pm200;...\right\}\)
mà -20<x<180
=> \(x\in\left\{0;40;80;120;160\right\}\)