This question is pertaining to College Algebra

Question

Solve by completing the square

 

x^2 - 2x - 2 = 0

Answer 1

x² - 2x - 2 = 0

x² - 2x = 2

 

Here's the trick.  The coefficient of the x term (-2x) is -2.  Add half that number (-2/2) squared, (-2/2)² = 1, to both sides of the equation.  This will make the left hand side of the equation into a perfect square.

 

x² - 2x + 1 = 2 + 1

(x-1)² = 3

 

Take the square root of both sides

 

x - 1 = ±√3

x = 1±√3

 

To check the answer plug both values (1+√3, 1-√3) into the original equation and verify that you get 0.