## Mathochism: Practical math

One woman’s attempt to revisit the math that plagued her in school. But can determination make up for 25 years of math neglect?

I’ve now had three geometry classes, and I’m embarrassed to report that I remember very little from high school. Sure, there are vague memories of trying to prove that an angle in a trapezoid is congruent to another angle, but how I would have even started that proof is just gone.

Actually, I suspect it was never there. The few bits I do remember are things I learned in my last three math classes, like the difference between complementary and supplementary angles, and the formula for finding the area of a sphere.

And then, there’s the very practical geometry I had to use back when I was a student pilot, and later, when I became a private pilot. For example, navigating crowded airspace involves using vectors. Most of my longer student trips, which involved at least two stops, involved a triangular route.

All airport runways are aligned according to the compass, which is based on the degrees in a circle. (Fun fact — LAX runways are usually used in the Southwestern direction, or 240.)

Banking, or turning, is done according to degrees — 15 degrees is a shallow bank, while 45 is considered steep. The flaps, which slow the plane down while you’re on final approach, are also measured in degrees — 10, 20, 30. (For any pilots reading, I mostly trained in a Cessna 152. Your measurements may vary.)

Then, there’s the angle of your nose as you climb or descend. The angle as you climb, known as the “angle of attack” is particularly important, since if your nose is too high, you can stall. If it is level, you won’t climb, and too low you will descend. The angle of attack isn’t something you can see from outside while you’re at the controls, but with enough training, you get a feel for how a good angle looks and feels (for one thing, you can’t see over the nose). Either way, it’s all about angles. I could go on about aviation and geometry forever, but I will stop there.

If I may go back to angles, though, I’ve been dealing with them a lot in a non-aviation setting. As I mentioned in my recent Hip Chronicles, you have to be very careful not to bend too much, or in the wrong direction, for at least three months after a hip replacement. The rule is nothing less than 90 degrees, so no acute angles for me! This meant that, for 12 weeks, I have been fretting over the angle of my hip whenever I sat down. Even lying down was fraught, since I had to be careful about how I was bending my knees. I couldn’t pull them up too far to my chest, even to exercise or moisturize or scratch my shin.

Fortunately, the restrictions are now off, so I’m acute again.

It’s odd, but until I wrote this, I never quite appreciated how much geometry I have used in my post-school life. It gives me hope that I will get through this class without losing my cool.

All text copyrighted by A.K. Whitney, and cannot be used without permission.