solve the equation by completing the square:

Question

x^2-9x-2=0

Answer 1

x^2-9x-2=0
x^2-9x + 81/4 = 2 + 81/4
(x-9/2)^2 = 89/4
x-9/2 = ±√89/2
x = 9/2 ±√89/2
x = (9 ± √89)/2