Square root of 28

The square root of 28 is ±5.2915. The positive value, 5.2915 is the solution of the equation x² = 28.

As defined, the square root is just the inverse of squaring a number, so, squaring 5.2915 will result in 28.  The square root of 28 is expressed as √28 in radical form, where the ‘√’  sign is called the “radical”  sign. In exponential form, it is written as (28)^1/2  
 

We can find the square root of 28 through various methods. They are:

• Prime factorization method

• Long division method

• Approximation/Estimation method

The prime factorization of 28 involves breaking down a number into its factors. Divide 28 by prime numbers, and continue to divide the quotients until they can’t be separated anymore.

After factoring 28, make pairs out of the factors to get the square root. If there exists numbers which cannot be made pairs further, we place those numbers with a “radical” sign along with the obtained pairs.

So, Prime factorization of 28 = 2 × 2 × 7   

But for 28, a pair of factor 2 can be obtained and a single 7 is remaining

So, it can be expressed as  √28 = √7  × √(2 × 2) = 2√7

 2√7 is the simplest radical form of √28

This is a method used for obtaining the square root for non-perfect squares, mainly. It usually involves the division of the dividend by the divisor, getting a quotient and a remainder too sometimes.

Follow the steps to calculate the square root of 28:

Step 1 : Write the number 28, and draw a bar above the pair of digits from right to left.
               
Step 2 : Now, find the greatest number whose square is less than or equal to. Here, it is
5, Because 5²=25 < 28

Step 3 : Now divide 28 by 5 (the number we got from Step 2) such that we get 5 as quotient, and we get a remainder. Double the divisor 5, we get 10 and then the largest possible number A1=2 is chosen such that when 2 is written beside the new divisor, 10, a 3-digit number is formed →102 and multiplying 2 with 102 gives 204 which is less than 300.

Repeat the process until you reach remainder 0.

We are left with the remainder, 9600 (refer to the picture), after some iterations and keeping the division till here, at this point 

             
Step 4 : The quotient obtained is the square root. In this case, it is 5.2…

Approximation or estimation of square root is not the exact square root, but it is an estimate. Here, through this method, an approximate value of square root is found by guessing.

Follow the steps below:

Step 1 : Identify the square roots of the perfect squares above and below 28.

Below : 25→ square root of 25 = 5     ……..(i)

 Above : 36 →square root of 36 = 6     ……..(ii)

Step 2 : Divide 28 with one of 5 or 6. 

If we choose 5, and divide 28 by 5, we get 5.6   …….(iii)

             
Step 3: Find the average of 5 (from (i)) and 5.6 (from (iii))

(5+5.6)/2 = 5.3

            
 Hence, 5.3 is the approximate square root of 28
 

• Exponential form: An algebraic expression that includes an exponent. It is a way of expressing the numbers raised to some power of their factors. It includes continuous multiplication involving base and exponent.Ex: 3 ⤬ 3 ⤬ 3 ⤬ 3 = 81 Or, 3 4 = 81, where 3 is the base, 4 is the exponent 

• Factorization: Expressing the given expression as a product of its factors. Ex: 52=2 ⤬ 2 ⤬ 13 

• Prime Numbers: Numbers which are greater than 1, having only 2 factors as →1 and Itself. Ex: 1,3,5,7,....

• Rational numbers and Irrational numbers: The Number which can be expressed as p/q, where p and q are integers and q not equal to 0 are called Rational numbers. Numbers which cannot be expressed as p/q, where p and q are integers and q not equal to 0 are called Irrational numbers. 

• perfect and non-perfect square numbers:Perfect square numbers are those numbers whose square roots do not include decimal places. Ex: 4,9,25 Non-perfect square numbers are those numbers whose square roots comprise decimal places. Ex :2, 8, 18