Solve x^2-6x+25 = 0 by completing the square.

First, subtract both sides by 25:

x^2 - 6x = -25

Because we're completing the square, we subtract both sides by 9:

x^2 - 6x - 9 = -34

(x - 3) = 5.831 (about)

x = 8.831

let's call the solutions x₁ = (5 - 2√7)/3 and x₂ = (5 + 2√7)/3

then the equation is (x-x₁)(x-x₂) = 0

if you fill that in you get a lot of numbers which you can recognize as ax²+bx+c=0.

step-by-step explanation:

you can see that a=1 (there is just an x²)

b = (-5 -2√7 + 2√7 - 5)/3 = -10/3

c = -2√7)/3 ) * (-5+2√7)/3) = -1/3

so your answer is 3x^2 – 10x – 1 = 0