Understand integers

Make sense of negative numbers before reaching for a rule.

Understand it

Make the idea make sense.

Negative integersless than zeroPositive integersgreater than zero-5-4-3-2-10123450 is neither positivenor negative
NegativePositive−3−2−10123Zero is neither positivenor negative
01

Start with a reference point

Zero gives a reference point. An elevation of −8 m is 8 m below sea level; +8 m is 8 m above it. A negative sign describes which side of the reference point a value lies on.

02

Compare positions, not just digits

On a horizontal number line, the number farther right is greater. −2 > −7 because −2 is farther right. Both numbers are less than zero.

03

Distance and value are different

−9 is less than −4, but |−9| is greater than |−4|. Distance from zero is never negative. Opposites have equal absolute values and add to zero.

04

An integer is a value, not a way of writing it

−5, 0 and 12 are integers. 2.5 is not. The decimal 3.0 represents the integer 3, and 6 ÷ 2 has the integer value 3. A decimal point or fraction notation alone does not tell you the value.

Words worth knowing
Integer
A number with a whole-number value: … −2, −1, 0, 1, 2, …
Opposite
A number the same distance from zero on the other side. Zero is its own opposite.
Absolute value
The distance from a number to zero, written with vertical bars: |−7| = 7.
Make the connection

One position. Three ways to describe it.

Move the point and compare the signed value, its opposite and its distance from zero.

Value−4
Opposite4
Absolute value4

Khan Academy

Pause before the next calculation. Predict the sign and explain the model, then compare the reasoning.

See the thinking

One step at a time.

Predict each next step, then reveal the explanation.

Example 1

Order −6, 3, −1, 0 from least to greatest

  1. Picture the values on a number line.
  2. The farthest-left value is −6, followed by −1, then 0, then 3.
  3. Least to greatest: −6 < −1 < 0 < 3.
Example 2

|−8| and the opposite of −8

  1. Absolute value asks for distance from zero: |−8| = 8.
  2. The opposite asks for the matching number across zero: the opposite of −8 is 8.
  3. These happen to be the same here. For +8, absolute value is still 8 but its opposite is −8.
Try together

A little support. Your thinking.

Which is greater: −4 or −9?

Your turn

Practice with purpose.

New questions, useful feedback and hints that build on your thinking.

Question 1 of 8Build confidence

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Progress stays on this device.Hints help you learn. First-try answers and supported answers are recorded separately.

Connections

In the real world

Temperature, sea level and bank balances all use a reference point. Always name what zero means.

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