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Explain why the square root of a number or variable can be either positive or negative.

User Ajthyng
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2 Answers

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25 votes

Answer/Step-by-step explanation:

The square root could be positive or negative because multiplying two negative numbers gives a positive number. The principal square root is the nonnegative number that when multiplied by itself equals a. The square root obtained using a calculator is the principal square root.

User Uri Goren
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21 votes

Answer:

Well, the answer is: it depends on what was printed in the problem. The principal square root symbol never has a negative output, so if the test maker printed that symbol, it’s restrictions have to be respected: all square roots then are positive.

Explanation:

a number y whose square (the result of multiplying the number by itself, or y ⋅ y) is x. For example, 4 and −4 are square roots of 16, because 4² = (−4)² = 16. Every nonnegative real number x has a unique nonnegative square root, called the principal square root, which is denoted by √(x), where the symbol √( ) is called the radical sign or radix.

User Ycr
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