I always wonder what is the real life use of studying geometry in school. You can parallel park your car perfectly.
Here is the step and you'll need a few pieces of information:
1. Your car's turning radius, r
2. The distance between the front and rear wheels, l
3. The distance from your front wheel to the corner of the front bumper, k
4. The width of the car you're trying to park behind, w
Run a simple calculation (see above illustration) and — voila! — you'll know just what to do.
Geometry can save you