Q:

# What is the square root of four?

A:

The square root of 4 is +2 or -2. The square root of a number can be either positive or negative. This is because the square of +2 is 4 and the square of -2 is also 4.

## Keep Learning

Similarly, the square root of 9 is either +3 or -3, and the square root of 16 is either +4 or -4. The square root of any number is obtained from the square of a number. If a number is a perfect square, then it has a perfect square root. Numbers, such as 1, 4, 9 and 16 are all perfect squares, hence they have a perfect square root. Numbers such as 2, 3, 5, 6 and 7 are not perfect squares; therefore, their square roots are not whole numbers.

Sources:

## Related Questions

• A: An extraneous root is a solution, or root, introduced into an intermediate equation while attempting to solve another equation. It does not, however, repre... Full Answer >
Filed Under:
• A: The square root of 289 is 17. The number 289 is a perfect square, as 17 times 17 is 289. The square of a negative number is a positive number, and this mea... Full Answer >
Filed Under:
• A: The more challenging Algebra 1 problems are quadratic equations of the form ax^2 +bx +c =0, where the general solution is given by the quadratic formula: x... Full Answer >
Filed Under:
• A: The expression (x^2 - 2x - 4) factors as (x + 1 - sqrt(5))*(x + 1 + sqrt(5)), where sqrt(5) is the square root of 5. This quadratic polynomial is factored ... Full Answer >
Filed Under:
PEOPLE SEARCH FOR