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Square Root.of 169 Calculator

Reviewed by Calculator Editorial Team

The square root of a number is a value that, when multiplied by itself, gives the original number. For example, the square root of 169 is 13 because 13 × 13 = 169. This calculator helps you find square roots quickly and accurately.

What is a Square Root?

The square root of a number x is written as √x. It is the non-negative number that, when multiplied by itself, equals x. For example:

  • √9 = 3 because 3 × 3 = 9
  • √16 = 4 because 4 × 4 = 16
  • √25 = 5 because 5 × 5 = 25

Square roots can be irrational numbers, meaning they cannot be expressed as simple fractions. For example, √2 ≈ 1.41421356237.

Square Root Formula

For a positive real number x, the square root is defined as:

√x = y where y × y = x and y ≥ 0

Properties of Square Roots

  • The square root of a perfect square is an integer (e.g., √16 = 4)
  • The square root of a non-perfect square is an irrational number
  • The square root of 0 is 0 (√0 = 0)
  • The square root of 1 is 1 (√1 = 1)

How to Calculate Square Root

There are several methods to calculate square roots:

Prime Factorization Method

  1. Factorize the number into its prime factors
  2. Group the prime factors into pairs
  3. Take one number from each pair and multiply them together

Example: Find √36

  1. 36 = 2 × 2 × 3 × 3
  2. Group into (2 × 2) and (3 × 3)
  3. Take one from each pair: 2 × 3 = 6

Long Division Method

  1. Group the digits into pairs from the decimal point
  2. Find the largest number whose square is less than or equal to the first group
  3. Subtract and bring down the next pair
  4. Double the quotient and find a digit to append to it
  5. Repeat until desired accuracy is reached

Note

For most practical purposes, using a calculator is the fastest and most accurate method.

Practical Applications

Square roots have many practical applications in various fields:

Mathematics

  • Solving quadratic equations
  • Calculating distances in coordinate geometry
  • Finding areas of geometric shapes

Engineering

  • Calculating forces and stresses
  • Determining electrical impedances
  • Analyzing wave propagation

Everyday Life

  • Measuring distances in navigation
  • Calculating areas of rooms and fields
  • Determining diagonal lengths of rectangles

Common Mistakes to Avoid

When working with square roots, it's easy to make these common mistakes:

Confusing Square and Square Root

Remember that 9² = 81 (9 squared) while √81 = 9 (square root of 81).

Assuming All Square Roots Are Integers

Not all numbers have integer square roots. For example, √2 is an irrational number.

Ignoring Negative Roots

While the principal square root is non-negative, some equations may require considering both positive and negative roots.

Important

The square root function (√) always returns the non-negative root. For negative numbers, use the imaginary unit i where √(-1) = i.

Frequently Asked Questions

What is the square root of 169?

The square root of 169 is 13 because 13 × 13 = 169.

How do I calculate the square root of a number?

You can use methods like prime factorization, long division, or simply use a calculator for quick results.

What is the difference between a square and a square root?

A square of a number is the result of multiplying the number by itself (e.g., 5² = 25). A square root is a number that, when multiplied by itself, gives the original number (e.g., √25 = 5).

Can the square root of a negative number be real?

No, in real numbers, the square root of a negative number is not defined. However, in complex numbers, it's represented using the imaginary unit i (e.g., √(-1) = i).