x^2 – 6x = 20
b=-6
to complete the square, add (b/2)^2 to each side
(b/2)^2 = (-6/2)^2=(-3)^2 =9
x^2 – 6x +9 = 20+9
(x+b/2) ^2 =29
(x-3)^2=29
take the square root of each side
x-3 = +- sqrt (29)
add 3 to each side
x = 3+- sqrt (29)
x = 3 + sqrt(29), x- sqrt(29)
Answer: -2.39, 8.39
