One of my New Year’s Resolutions is to relearn math. I’ve begun by learning about positive and negative numbers. Positive numbers are easy to understand; they are everywhere. We count with positive numbers. We measure our height with positive numbers and our weight (although a negative number here would be good in my case.)
Temperatures below zero are expressed as negative numbers. When you spend more money than you have, you have a negative balance.
The number line is used to express positive and negative numbers. Zero lives at the center of the line. Positive numbers increase to the right of zero and negative numbers increase in value to the left of zero.
There are other ways to visualize positive and negative numbers. A thermometer uses positive and negative numbers to display temperatures. A piano keyboard represents the concept of positive and negative numbers in the sense that negative numbers are smaller than positive numbers. The strings that produce the bass notes (left side of the keyboard) vibrate at a slower rate (less vibrations per second) than the higher (treble) notes (more vibrations per second) located at the right side of the keyboard.
Color can also represent the concept of positive and negative values. The brighter the color, the higher the positive number (more brightness, less darkness). The darker the color, the higher the negative number (more darkness, less brightness).