In answer to your question, depending on how low your car is(i.e get right underneath and jack it up from a strong chassis point) or you can jack it up on the Sills, (should be about 3-4 inches from the corner of arch) then find an appropriate place on the body of the car to place an axle stand.
Dont go under the car with just the trolley jack holding it up, because they can leak oil slowly while your under the car, fail and collapse.
Especially the cheap ones.