“Let me tell you a story,” I said, still smiling after the requisite groans swept through the class.

“Back when I was in elementary school — maybe when I was 8 years old — I would always walk home near a church. It sort of looked like this…”

“But instead of walking along the paved roads, I would always cut across the lawn of the church. And for the longest time, I wondered why this was the best path. How did you know cutting across the lawn was the shortest way of getting home? I mean, how did you really know? How does one go about actually proving it?”

“It wasn’t until I looked into the so-called triangle inequality…”

“…that I realized, ‘Hey, so that’s why I always made it home on time to watch tv!’. I always thought that was neat. Then again, what growing boy hasn’t thought of this?”

“Did you walk home alone?”, asked a student.

Before I had a chance to answer, another one quipped, “Obviously.”

There was little I could say or do that would drown out the loud snickering that ensued.