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Absolute Value Calculator – |x| with Properties

Quick answer

Evaluate |x| instantly: |−12|=12, |5|=5, |3−9|=6.

  • See the piecewise rule, distance meaning and simplifications of |x|² and √(x²).

Figures are estimates from this calculator’s standard formula — adjust the inputs in the tool below for your exact number.

How the Absolute Value Calculator Works

|x| = x if x ≥ 0; |x| = −x if x < 0

The absolute value strips a number’s sign, leaving its distance from zero: |−12| = 12, |5| = 5, and for expressions first evaluate inside — |3−9| = |−6| = 6. The calculator applies the piecewise definition, telling you which branch fired, so the habit "absolute value never negative" is reinforced with each run. It also simplifies the classic identities: |x|² = x² (both equal 9 for x = −3), √(x²) = |x|, and |a·b| = |a|·|b| — so |−4×7| = 28. Magnitude comparisons print the distance between two points |a−b|, e.g. |−7−3| = 10, which is the number-line gap. For inputs in scientific or decimal form the result keeps full precision, and the tool notes the special case |0| = 0, the only value whose absolute value equals its negative.

  1. 1

    Type a number or expression

    Such as -12, 3-9, or -4×7

  2. 2

    Evaluate inside first

    Expressions reduce to a single value before the bars apply

  3. 3

    Apply the piecewise rule

    Positive stays, negative flips — the active branch is shown

  4. 4

    Review the identities

    x², √(x²) and |a−b| distance forms accompany the result

Use Cases

Checking Homework

Verify |3−9| = 6 and similar drill problems instantly

Data Cleaning

Measure magnitude of deviations from a target value

Complex Number Magnitude

Seed the |z| habit that generalizes to |3+4i| = 5

Tips

  • 1

    Evaluate the inside completely before dropping the sign

  • 2

    |x|² = x² always, but √(x²) = |x|, not x

  • 3

    |a−b| is the distance between a and b on the number line

Common Mistakes

  • Answering |3−9| as −6 — inside first, then the bars

  • Assuming |x| can output negatives; the minimum is 0

  • Writing √(x²) = x, wrong for x = −3 where it equals 3

  • Distributing bars over addition: |−3+5| is 2, not 8

FAQs

What is |−12|?

12 — the distance from −12 to zero.

What is |3−9|?

Evaluate inside: 3−9 = −6, so |−6| = 6.

Does |x|² equal x²?

Yes. For x = −3 both give 9. But √(x²) = |x| = 3, not −3.

What is |−4 × 7|?

28. Multiplication respects the bars: |−4|×|7| = 4×7.

Can absolute value ever be negative?

No. The output is a distance; the smallest possible value is |0| = 0.