Street Trigonometry and White Canes
I used to work as a cabinet maker during the day and teach math at the community college at night. The guys I worked with at the cabinet shop were mostly Spanish speaking immigrants. Many of them hadn't finished high school and none of them had been to college. A few had been in prison. They didn't think they had the brains to understand college level courses. There's a quick little trick I know to figure out the degree of any angle if you know the lengths of the sides on either side of the angle. Suppose you want to cut a 6" by 8" board diagonally. What angle would you set your saw to make the cut? The trick is to use inverse tan (length/width), or inverse tan 6/8. Just plug it into the scientific calculator on your smart phone and make sure your calculator is in degrees instead of radians and you'll get the answer: just a kiss under 36.87 degrees. It took me forever to get college students to understand this concept. The immigrant workers in the cabinet sh...