게 먹히다

work out cheap; or be effective

먹히다 is the passive of 먹다 "eat", and with a "-게" adverb it splits into two idioms. Five of these lines are about cost: 싸게 먹히다 and 저렴하게 먹히다, literally "it gets eaten cheaply", meaning the total works out low — cheapest for the company, over ten years it comes cheap. The other two are about a tactic landing: Beijing's negotiating strategy worked perfectly, and "how does this work?" There is no shared metaphor between the two; treat them as separate phrases.