San Francisco is quiet expensive with rents around $1,800-$2,000+ for an unfurnished 1br (furnished is likely to be a lot more).
East bay is cheaper with prices around $1,000-$1,500.
South bay is somewhere in the middle.
It probably means that you need to use the given postulates and known theorems about right-angled triangles to come up with a way or formula for generating such triangles.