Math 6A ( Periods 2 & 5)

Absolute Value 6.4

The absolute value of a number is the distance between the number and ZERO on a number line. The absolute value of a number a is written as │a│.

│-2│ = 2       │2│  = 2

  │a│ is read “ the absolute value of a.”

Distance is always positive OR zero!

When you write the notation for the absolute value, it means “take the absolute value of the number inside the symbols! “

When graphing  │-5│  first find the value of │-5│, which is 5, then graph it.  Make sure to identify the graph with the given number. In this case, │-5│

So we could conclude that  │-5│> 2.

Write these numbers in order from least to greatest.

│-12│, -8, -10, │6│, │-4│

We would get:

-10, -8, │-4│, │6│, │-12│

Which is greater  -50 or 25?   25

Now, which of those two has the greater absolute value?

 This time its -50 since

│25│= 25   and │-50│=50

The coldest possible temperature is called absolute zero. It is represented by 0 K on the Kelvin temperature scale.  See Page 273

Tell whether the statement is always, sometimes, or never true.

The absolute value of a number is greater than the number.  Sometimes- If the number is negative then its absolute value is greater, but if it is positive or zero then it is equal to its absolute value.

The absolute value of a negative number is positive. Always- The absolute value is the positive distance from zero on a number line.

The absolute value of a positive number is its opposite. Never- The absolute value of appositive number is the number itself