What is the negative square root of 27? Algebra Radicals and Geometry Connections Simplification of Radical Expressions 1 Answer George C. Jul 14, 2015 The negative square root of 27 is -sqrt(27) = -3sqrt(3) Explanation: x^2=27 has two solutions, which we call +-sqrt(27) sqrt(27) denotes the positive square root. -sqrt(27) is also a square root of 27, which we call the negative square root of 27 If a, b >= 0 then sqrt(ab) = sqrt(a)sqrt(b). So: -sqrt(27) = -sqrt(3^2*3)=-sqrt(3^2)sqrt(3) = -3sqrt(3) Answer link Related questions How do you simplify radical expressions? How do you simplify radical expressions with fractions? How do you simplify radical expressions with variables? What are radical expressions? How do you simplify root{3}{-125}? How do you write ""^4sqrt(zw) as a rational exponent? How do you simplify ""^5sqrt(96) How do you write ""^9sqrt(y^3) as a rational exponent? How do you simplify sqrt(75a^12b^3c^5)? How do you simplify sqrt(50)-sqrt(2)? See all questions in Simplification of Radical Expressions Impact of this question 8072 views around the world You can reuse this answer Creative Commons License