Square Root of Negative Numbers Practice Problems

Master square roots of negative numbers with practice problems. Learn why negative numbers have no real square roots and solve related exercises step-by-step.

πŸ“šWhat You'll Practice and Master
  • Identify why negative numbers have no real square roots
  • Solve square root problems involving negative numbers
  • Distinguish between positive and negative square root scenarios
  • Apply the square root definition to determine when solutions exist
  • Practice recognizing 'no solution' cases in square root problems
  • Master the concept that squared positive numbers are always positive

Understanding Square Root of a Negative Number

Complete explanation with examples

Square Root of a Negative Number

There is no root of a negative number since any positive number raised to the second power will result in a positive number.

Detailed explanation

Practice Square Root of a Negative Number

Test your knowledge with 10 quizzes

\( \sqrt{196}= \)

Examples with solutions for Square Root of a Negative Number

Step-by-step solutions included
Exercise #1

100= \sqrt{100}=

Step-by-Step Solution

The task is to find the square root of the number 100. The square root operation seeks a number which, when squared, equals the original number. For any positive integer, if x2=100 x^2 = 100 , then x x should be our answer.

Step 1: Recognize that 100 is a perfect square. This means there exists an integer x x such that xΓ—x=100 x \times x = 100 . Generally, we recall basic squares such as:

  • 12=1 1^2 = 1
  • 22=4 2^2 = 4
  • 32=9 3^2 = 9
  • and so forth, up to 102 10^2

Step 2: Checking integers, we find that:

102=10Γ—10=100 10^2 = 10 \times 10 = 100

Step 3: Confirm the result: Since 10Γ—10=100 10 \times 10 = 100 , then 100=10 \sqrt{100} = 10 .

Step 4: Compare with answer choices. Given that one of the choices is 10, and 100=10 \sqrt{100} = 10 , choice 1 is correct.

Therefore, the square root of 100 is 10.

Answer:

10

Video Solution
Exercise #2

64= \sqrt{64}=

Step-by-Step Solution

To solve this problem, we'll follow these steps:

  • Step 1: Recognize what finding a square root means
  • Step 2: List known perfect squares to identify which one results in 64
  • Step 3: Verify the square root by calculation

Now, let's work through each step:
Step 1: To find the square root of 64, we seek a number that, when multiplied by itself, equals 64.
Step 2: Consider the sequence of perfect squares: 12=1 1^2 = 1 , 22=4 2^2 = 4 , 32=9 3^2 = 9 , 42=16 4^2 = 16 , 52=25 5^2 = 25 , 62=36 6^2 = 36 , 72=49 7^2 = 49 , 82=64 8^2 = 64 .
Step 3: We see that 82=64 8^2 = 64 . Therefore, the square root of 64 is 8.

Therefore, the solution to this problem is 8 8 .

Answer:

8

Video Solution
Exercise #3

9= \sqrt{9}=

Step-by-Step Solution

To solve this problem, we want to find the square root of 9.

Step 1: Recognize that a square root is a number which, when multiplied by itself, equals the original number. Thus, we are seeking a number x x such that x2=9 x^2 = 9 .

Step 2: Note that 9 is a common perfect square: 9=3Γ—3 9 = 3 \times 3 . Therefore, the square root of 9 is the number that, when multiplied by itself, gives 9. This number is 3.

Step 3: Since we are interested in the principal square root, we consider only the non-negative value. Hence, the principal square root of 9 is 3.

Therefore, the solution to the problem is 3 3 .

Answer:

3

Video Solution
Exercise #4

49= \sqrt{49}=

Step-by-Step Solution

To solve this problem, we follow these steps:

  • Step 1: Understand that finding the square root of a number means determining what number, when multiplied by itself, equals the original number.
  • Step 2: Identify the numbers that could potentially be the square root of 4949. These are Β±7 \pm7, but by convention, the square root function typically refers to the non-negative root.
  • Step 3: Calculate 7Γ—7=497 \times 7 = 49. This confirms that 49=7 \sqrt{49} = 7.
  • Step 4: Verify using the problem's multiple-choice answers to ensure 77 is among them, confirming choice number .

Therefore, the solution to the problem 49 \sqrt{49} is 7 7 .

Answer:

7

Video Solution
Exercise #5

36= \sqrt{36}=

Step-by-Step Solution

To solve this problem, we'll follow these steps:

  • Step 1: Understand the definition of a square root.
  • Step 2: Identify which integer, when squared, gives 36.
  • Step 3: Verify this integer meets the required condition.
  • Step 4: Choose the correct answer from the given choices.

Now, let's work through each step:
Step 1: A square root of a number is a value that, when multiplied by itself, gives the original number. Here, we want y y such that y2=36 y^2 = 36 .
Step 2: We test integer values to find which one squared equals 36. Testing y=1,2,3,4,5, y = 1, 2, 3, 4, 5, and 6 6 gives:
- 12=1 1^2 = 1
- 22=4 2^2 = 4
- 32=9 3^2 = 9
- 42=16 4^2 = 16
- 52=25 5^2 = 25
- 62=36 6^2 = 36

Step 3: The integer 6 6 satisfies 62=36 6^2 = 36 . Therefore, 36=6 \sqrt{36} = 6 .

Step 4: The correct choice from the given answer choices is 6 (Choice 4).

Hence, the square root of 36 is 6 \mathbf{6} .

Answer:

6

Video Solution

Frequently Asked Questions

Why can't negative numbers have square roots?

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Negative numbers cannot have real square roots because any positive number multiplied by itself (squared) always produces a positive result. Since there's no positive number that when squared gives a negative result, negative numbers have no real square roots.

What should I write when asked to find the square root of a negative number?

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When solving problems involving the square root of negative numbers, your answer should be 'no solution' or 'no real solution.' This is because no real number exists that satisfies the condition.

Is the square root of -9 equal to -3?

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No, the square root of -9 is not -3. The square root of -9 has no real solution because (-3)Β² = 9, not -9. Remember that squaring any real number always gives a positive result.

How do I solve square root problems with negative numbers step by step?

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Follow these steps: 1) Identify if the number under the square root sign is negative, 2) Recall that square roots of negative numbers have no real solutions, 3) Write 'no solution' or 'undefined in real numbers' as your answer.

What's the difference between √9 and √-9?

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√9 = 3 because 3² = 9, while √-9 has no real solution because no real number when squared equals -9. This demonstrates why positive numbers have square roots but negative numbers don't.

Can calculators find square roots of negative numbers?

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Standard calculators will show an error when trying to find square roots of negative numbers because these have no real solutions. Some advanced calculators may display complex numbers, but in basic algebra, the answer is 'no solution.'

Why do exam questions include square roots of negative numbers?

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Teachers include these problems to test your understanding of when square roots exist and when they don't. It's important to recognize that not all mathematical expressions have real number solutions.

What are some common examples of negative square root problems?

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Common examples include: √-1 (no solution), √-4 (no solution), √-16 (no solution), and √-25 (no solution). In each case, the answer is 'no real solution' because no positive number squared gives a negative result.

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