expression, ichidan verb
weigh one thing against another; compare the merits of two options
Figurative use: mentally weighing or comparing two choices, often to decide which is better. The literal sense of physically weighing something on scales is rare in modern Japanese.
進学と就職を天秤にかけて、結局大学に行くことにした。
I weighed going on to higher education against getting a job, and in the end decided to go to university.
Choose investments by weighing risk against return.
expression, ichidan verb
try to have it both ways; play a double game
Idiomatic: trying to keep two conflicting options open at once, often with a negative connotation of opportunism or hedging bets.
彼は二つの会社を天秤にかけて、どちらからも内定をもらおうとしている。
He's trying to have it both ways with two companies, aiming to get a job offer from both.
そんなふうに天秤にかけるような態度はよくない。
An attitude like that, trying to play both sides, isn't good.