Negative numbers and integers

Carry the number line on to the left of zero. Show temperatures below zero and depths below sea level, then add and subtract with jumps.

Guide

Numbers to the right of zero are positive numbers and numbers to the left of zero are negative numbers. Zero is neither positive nor negative. Together they are the integers.

The minus sign always goes on the left: −4 is "negative four" (or "minus four"). A temperature of 4 degrees below zero is written −4 °C. 4 and −4 are the same distance from zero, on opposite sides.

On the number line, numbers get bigger from left to right. So the further left a number is, the smaller it is: −8 is less than −3.

Adding a positive number is a jump to the right. Subtracting a positive number is a jump to the left. The arc over the line shows the jump.