Square Root of 80

Calculate √80 instantly — exact value, step-by-step explanation, and properties.

√80 =
8.9442719100
Simplified: 4√5
≈ Irrational Number

How to Calculate √80

The square root of 80 is approximately 8.9442719100. Since 80 is not a perfect square, its square root is an irrational number. We know that √64 = 8 and √81 = 9, so √80 falls between 8 and 9. The simplified radical form is 4√5. To estimate manually: start with 8.9, then refine using the Babylonian method — guess a value, divide 80 by it, average the result with your guess, and repeat.

The Babylonian Method (Step by Step)

  1. Start with an initial guess. Since √64 = 8 and √81 = 9, a good starting guess is 8.5.
  2. Divide 80 by your guess: 80 ÷ 8.5 = 9.4118
  3. Average the result with your guess: (8.5 + 9.4118) ÷ 2 = 8.955882
  4. Repeat with the new estimate until you reach the desired precision.
√80 ≈ 8.9442719100

Properties of √80

Perfect Square?

No

80 is not a perfect square. Its root is irrational.

Decimal Value

8.9442719100

Rounded to 10 decimal places.

Simplified Form

4√5

Simplified by extracting perfect square factors from the radicand.

Square Root Symbol

√80

Also written as 80^(1/2) or 80^0.5 in programming.

Related Square Root Values

Reference table of square roots near 80 for quick comparison.

Number Square Root Perfect Square? Simplified
√81 9 Yes 9
√75 8.660254 No 5√3
√72 8.485281 No 6√2
√90 9.486832 No 3√10
√64 8 Yes 8
√100 10 Yes 10
√50 7.071067 No 5√2
√49 7 Yes 7
√48 6.928203 No 4√3
√45 6.708203 No 3√5

Frequently Asked Questions

What is the square root of 80?

The square root of 80 is approximately 8.9442719100. This is an irrational number, which can be written in simplified radical form as 4√5.

Is 80 a perfect square?

No, 80 is not a perfect square. Its square root (8.9442719100...) is an irrational number that cannot be expressed as a simple fraction.

How do you calculate √80 by hand?

To calculate √80 by hand, use the Babylonian method: (1) Make an initial guess — since √64 = 8 and √81 = 9, start with 8.5. (2) Divide 80 by your guess. (3) Average the result with your guess. (4) Repeat steps 2-3 until you reach desired precision.

What is √80 in simplified radical form?

√80 can be simplified to 4√5. This is found by factoring out the largest perfect square from 80.

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