Math Dictionary / Square Root

Square Root

A square root of a number is a value that multiplies by itself to make that number.

Number SystemGrade 8Algebra 1GEDSATACT

What it means

The square root of 36 is 6 because 6 x 6 = 36.

Also called: radical

Examples

sqrt(25) = 5
sqrt(81) = 9
sqrt(2) is about 1.414

Common mistake

The principal square root is non-negative. sqrt(49) means 7, not -7.

Try one

Question: What is sqrt(144)?

Show answer

12, because 12 x 12 = 144.

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