Keep the quadratic formula close at hand. Geometry is like owning a toolbox. You need to have tools to solve problems. Geometry is like using a toolbox. You need to know what tools are in your box and how to use each one of them.
Geometry is like using a toolbox effectively.
You need to know what you're trying to accomplish, and you need to know which tools will get the job done. Geometry is like maintaining a toolbox. Geometry is like being responsible for a toolbox. Use it or lose it. Use it properly or else the tools inside will come back to bite you through improper application.