Square Roots

When a number is raised to the second power, we say that the number is squared. For example, 42=4(4) is referred to as “4 squared.” Often we need to know what number was squared in order to produce some value a. If we can find such a number, we call that number a square root of a. In this lesson you will learn about how to take square roots, and some of their properties.


Defining and computing square roots

The number 5 is a square root of 25, because 52=25. The number 5 is another square root of 25, because (5)2=25.

Question 1 of 8. Find the two square roots of 4. and
Find the square roots of 36. and
Is the square of a positive number positive, negative, or zero? (For example, is 32=3(3) positive, negative, or zero?)
Is the square of a negative number positive, negative, or zero? (For example, is (4)2=(4)(4) positive, negative, or zero?)
Is 02 positive, negative, or zero?
Can the square of a real number be negative?
Is it possible for a negative number to have a real square root?
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