I had a math(s) teacher when I was about 11, who would use the phrase "sit on your protractor" to talk about getting inside a geometry problem and asking yourse

I had a math(s) teacher when I was about 11, who would use the phrase "sit on your protractor" to talk about getting inside a geometry problem and asking yourself "does my solution roughly make sense". I still think in those terms, asking whether the answer to a problem, whether a SWAG, estimate, or careful calculation, could actually be correct