 The absolute value of a number is its size, when we don't care whether it's positive or negative. For instance, if the temperature fell from negative four degrees to negative twelve degrees, we might ask "how many degrees did the temperature drop?" We want an answer of 8 degrees, not negative 8 degrees. Absloute value can also be thought of as how far from zero a number is. We might be asked, for example, how far from zero the temperature is this afternoon. If the answer is 20, we don't care whether the temperature is +20 or -20, since both are 20 degrees from the zero point. The absolute value of a number is just its magnitude, or size, without a positive or negative sign. Here are some examples: This means that absolute value just removes the sign from a number. In later Math courses you'll learn that sometimes when you solve a problem, you get two answers. A math problem, for example, might solve to give both 15 and -15 as solutions. But the problem was about time, and a 'negative time' wouldn't make sense. We want a positive answer. So we want the absolute value of the answer, which is just 15. There is a symbol for 'absolute value' so you won't have to write the words every time. The absolute value of -6 is written as |-6|. The absolute value of -6 is 6 is written as |-6| = 6. The symbols are two vertical lines surrounding the number. Here are more examples using the symbols: |-13| = 13 |+23| = 23 |-1| = 1 |0| = 0 |-100| = 100 Your calculator may do absolute value, and show the bars on-screen, but the key you press is often labelled 'abs'. |