Last updated on May 26th, 2025
If a number is multiplied by itself, the result is a square. The inverse of this process is finding the square root. Square roots are used in various fields such as engineering, finance, and physics. Here, we will discuss the square root of 139.25.
The square root is the inverse operation of squaring a number. 139.25 is not a perfect square. The square root of 139.25 can be expressed in both radical and exponential forms. In radical form, it is expressed as √139.25, whereas in exponential form it is (139.25)(1/2). The square root of 139.25 is approximately 11.799, which is an irrational number because it cannot be expressed as a simple fraction p/q, where p and q are integers and q ≠ 0.
The prime factorization method is used for perfect square numbers. However, for non-perfect square numbers, methods such as the long-division method and approximation method are used. Let us now learn the following methods:
The long division method is particularly useful for non-perfect square numbers. Here is how to find the square root using the long division method, step by step:
Step 1: Group the digits of 139.25 from right to left into pairs: 39|25.
Step 2: Find a number whose square is less than or equal to 39. The number is 6 (since 6 x 6 = 36).
Step 3: Subtract 36 from 39, and bring down 25 to get 325.
Step 4: Double the divisor (6) to get 12. Now find a digit n such that 12n * n is close to 325. The digit n is 2 (since 122 x 2 = 244).
Step 5: Subtract 244 from 325 to get 81.
Step 6: Add a decimal point to the quotient, and bring down 00 to get 8100.
Step 7: The new divisor is 124. Find a digit n such that 124n * n is close to 8100. The digit n is 6 (since 1246 x 6 = 7476).
Step 8: Subtract 7476 from 8100 to get 624.
Step 9: Continue the process to get more decimal places.
So, the square root of 139.25 is approximately 11.799.
The approximation method is a simpler way to find the square root of a number:
Step 1: Identify the two perfect squares between which 139.25 lies. The closest perfect squares are 121 (112) and 144 (122).
Step 2: √139.25 lies between 11 and 12.
Step 3: Use interpolation to estimate: (Given number - smaller perfect square) / (Larger perfect square - smaller perfect square) = (139.25 - 121) / (144 - 121)
This results in approximately 0.799. Adding the initial whole number 11 to the decimal point, we get 11 + 0.799 = 11.799.
So, the approximate square root of 139.25 is 11.799.
Students often make mistakes while finding square roots, such as ignoring the negative square root or skipping steps in the long division method. Here are a few common mistakes students make:
Can you help Max find the area of a square if its side length is given as √139?
The area of the square is approximately 139 square units.
The area of a square = side^2.
Given the side length as √139, Area = (√139) × (√139) = 139.
Therefore, the area of the square is approximately 139 square units.
A square-shaped garden measures 139.25 square meters in area. If each side is √139.25 meters, what is the area of half of the garden?
69.625 square meters
To find the area of half the garden, divide the total area by 2: 139.25 / 2 = 69.625 square meters.
So, half of the garden measures 69.625 square meters.
Calculate √139.25 × 4.
47.196
First, find the square root of 139.25, which is approximately 11.799.
Then multiply by 4: 11.799 × 4 = 47.196.
So, √139.25 × 4 = 47.196.
What will be the square root of (140 + 5)?
The square root is 12.
First, find the sum of (140 + 5): 140 + 5 = 145
The square root of 145 is approximately 12.042, but rounding to the nearest whole number gives 12.
Therefore, the square root of (140 + 5) is approximately ±12.
Find the perimeter of a rectangle if its length ‘l’ is √139 units and the width ‘w’ is 39 units.
The perimeter of the rectangle is approximately 101.598 units.
Perimeter of a rectangle = 2 × (length + width).
Perimeter = 2 × (√139 + 39)
≈ 2 × (11.789 + 39)
≈ 2 × 50.789
= 101.598 units.
Jaskaran Singh Saluja is a math wizard with nearly three years of experience as a math teacher. His expertise is in algebra, so he can make algebra classes interesting by turning tricky equations into simple puzzles.
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