How do you solve the quadratic 10x^2+7=-310x2+7=−3 using any method? Precalculus Linear and Quadratic Functions Completing the Square 1 Answer Aditya Banerjee. Oct 29, 2016 Answer is x=+-i=+-sqrt-1x=±i=±√−1. Explanation: 10x^2+7=-310x2+7=−3 :.10x^2=-10 :.x^2=-1 :. x^2=i^2 [ i is imaginary number, i=sqrt-1] :.x=+-i :.x=+-sqrt-1. (answer). 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 1585 views around the world You can reuse this answer Creative Commons License