My teachers from high school were right. As students we thought classes like geometry were useless but twenty years after taking the class, I used geometry today. I needed to figure out the incline of a touch panel unit used by the air traffic controllers so we could replicate one for our system. It's a rectangle shape recessed into a table with the triangle portion of it sticking above the table (the other half below the table). I took the measurements of the rectangle, figured out the length of the side opposite of the right triangle, figured out the other two angles and bam, got the incline.
Once over twenty years time.