How do you solve the quadratic #9x^2+8=-35# using any method? Precalculus Linear and Quadratic Functions Completing the Square 1 Answer Alan N. Aug 21, 2016 #x=+-sqrt(43)/3i# Explanation: #9x^2+8=-35# #9x^2 = -43# #x^2 = -43/9# #x =+- sqrt(-43/9) = +-sqrt(43)/sqrt(9)i# #x=+-sqrt(43)/3i# Answer link Related questions What does completing the square mean? How do I complete the square? Does completing the square always work? Is completing the square always the best method? Do I need to complete the square if #f(x) = x^2 - 6x + 9#? How do I complete the square if #f(x) = x^2 + 4x - 9#? How do I complete the square if the coefficient of #x^2# is not 1? How do I complete the square if #f(x) = 3x^2 + 12x - 9#? If I know the quadratic formula, why must I also know how to complete the square? How do I use completing the square to describe the graph of #f(x)=30-12x-x^2#? See all questions in Completing the Square Impact of this question 1498 views around the world You can reuse this answer Creative Commons License