**The square root of 121 is 11 or negative 11.** The factors of 121 are 11 x 11. Similarly, negative 11 x negative 11 is also 121. To obtain an exact square root, the number must be a perfect square.

If a number is not a perfect square, the square root is a decimal. For example, the number 50 is not a perfect square. The square root of 50 is 5?2 or negative 5?2. Similarly, the square root of 100 is 10 or negative 10, but the square root of 125 is 5?5 or negative 5?5. This solution can also be expressed as a decimal as ?50 = 7.07 and ?125 = 11.18.