Square Root of 175

The square root of 175 is 5√7 in simplest radical form, or about 13.2287565553 as a decimal.

Whole numbers, decimals or fractions like 9/16. Negative numbers have no real root.
Simplest radical form
5√7
Decimal
13.2287565553
Both real square roots
±13.2287565553x² = 175 has two real solutions
Between
13² = 169 and 14² = 196so the root is between 13 and 14
Perfect power?
No
√17513.2287565553= 5√7

Show the work

  1. Prime-factor the radicand: 175 = 52 × 7 = (52) × 7.
  2. Each pair of identical factors comes out of the radical as a single factor: √175 = 5√7.
  3. Decimal value: √175 ≈ 13.2287565553.
  4. Check: 13.22875655532 ≈ 175.

√175 at a glance

Exact value
5√7
Decimal (10 places)
13.2287565553
Rounded
13.2 · 13.23 · 13.229
Perfect square?
No — between 13² and 14²
Rational?
Irrational
Both square roots
±13.228757
Prime factorization
5² × 7
Cube root
5.593445

How to simplify √175

Look for the largest perfect square that divides 175. Here it is 25 (5²), because 175 = 25 × 7 and 7 has no square factor left:

√175 = √(25 × 7) = √25 × √7 = 5√7

The prime factorization tells the same story: 175 = 5² × 7. Each pair of equal primes leaves the radical as one factor, so 5 comes out and 7 stays inside.

Check: (5√7)² = 5² × 7 = 25 × 7 = 175. As a decimal, 5√7 = 5 × 2.6457513111 ≈ 13.2287565553.

Where √175 sits between perfect squares

169 = 13² and 196 = 14² are the nearest perfect squares, so √175 lies between 13 and 14. 175 is 6 above 169 and 21 below 196, so the root is closer to 13.

√175 ≈ 13 + (175 − 169) ÷ (196 − 169) = 13 + 6/27 ≈ 13.2222
  • Straight line between 169 and 196: 13.2222 (0.05% low)
  • Tangent from 13, i.e. 13 + 6 ÷ 26: 13.2308 (0.02% high)
  • Tangent from 14, i.e. 14 − 21 ÷ 28: 13.2500 (0.16% high)

For √175 the tangent at 13 wins, missing by only 0.002. Tangent estimates shine when the number sits close to a perfect square — here 175 is just 6 above 169.

1313² = 1691414² = 196√175 ≈ 13.2288
√175 on a number line, with tenths marked between 13 and 14.

Finding √175 with the Babylonian method

If a guess is too big, 175 ÷ x is too small by about the same amount, so their average lands much closer. In fact an error of e shrinks to roughly e² ÷ (2√175) in one step.

xnext = (x + 175 ÷ x) ÷ 2

Start from the nearest whole number, 13 (13² = 169):

StepGuess x175 ÷ xAverageCorrect decimals
113.000000000013.461538461513.23076923082
213.230769230813.226744186013.22875670846
313.228756708413.228756402213.2287565553all 10 shown

The count of correct decimals went 2, 6 and all 10 over 3 steps — roughly doubling each time — until the guess matched √175 = 13.2287565553 to every decimal shown.

√175 as a continued fraction

Every irrational square root has a continued fraction that repeats. For √175 the pattern is [13; 4, 2, 1, 2, 4, 26] with the block of 6 terms after the semicolon repeating forever. A pattern that never ends is one more proof that √175 is irrational.

Cutting the continued fraction off early gives the best fractions for approximating the root — no fraction with a smaller denominator comes closer:

FractionDecimalError
13/113.00000000002.3 × 10⁻¹
53/413.25000000002.1 × 10⁻²
119/913.22222222226.5 × 10⁻³
172/1313.23076923082.0 × 10⁻³
463/3513.22857142861.9 × 10⁻⁴
2,024/15313.22875816991.6 × 10⁻⁶

The same fractions solve Pell’s equation, x² − 175y² = 1. Its smallest solution in positive whole numbers is x = 2,024, y = 153.

√175 in geometry and everyday measurements

  • A square room or garden bed covering 175 square feet measures about 13.23 ft (13 ft 3 in) along each wall.
  • 175 is not a sum of two whole-number squares — the prime factor 7 (one less than a multiple of 4) appears an odd number of times, which rules that out — so √175 is never the diagonal of a rectangle with whole-number sides. It is not a sum of three positive squares either, so no whole-number box has √175 as its space diagonal.
  • Since √175 = 5√7, a length of √175 is exactly 5 copies of the length √7 laid end to end.
RootSimplest formDecimalPerfect square?
√1722√4313.1149No
√173√17313.1529No
√174√17413.1909No
√1755√713.2288No
√1764√1113.2665No
√177√17713.3041No
√178√17813.3417No
  • The cube root of 175 is about 5.593445.
  • Four times the radicand doubles the root: √700 = 2 × √175 ≈ 26.457513.

Frequently asked questions

What is the square root of 175?

The square root of 175 is 5√7 in simplest radical form, which is about 13.2287565553. The negative root, −13.228757, also squares to 175.

Is the square root of 175 rational or irrational?

Irrational. 175 is not a perfect square — it falls between 169 and 196 — and the square root of any whole number that is not a perfect square cannot be written as a fraction.

Can √175 be simplified?

Yes. The largest perfect square dividing 175 is 25, so √175 = √25 × √7 = 5√7.

What is √175 rounded to two decimal places?

√175 ≈ 13.23 to two decimal places (13.2 to one, 13.229 to three). Check: 13.23² = 175.0329, close to 175.

Need a different value? Use the Square root calculator, or browse the Square roots 1–1,000.