It's not unusual to think that the English sections of the SAT are subjective. It can sometimes feel like you're being expected not so much to read the passages as to read the test-makers' minds. But make no mistake: the logic behind the questions is just as rigorous as the logic of a system of equations.
In fact, a system of equations is the perfect metaphor for how to think about each passage you read, on the SAT or elsewhere.
To follow along with today's Test Crushers Chronicle, download the College Board's SAT Practice app, and find the problem for November 14, 2017 (Reading).