Question 422040
What are the solutions to the equation x^2 - 6x + 5 = -8? 
:
Complete the square to solve this one
x^2 - 6x + __ = -8 - 5
:
x^2 - 6x + __ = -13
:
To complete the square divide the coefficient of x by 2 and square it: 3^2 = 9
Add 9 to both sides
x^2 - 6x + 9 = -13 + 9
:
x^2 - 6x + 9 = -4
Which is
(x - 3)^2 = -4
:
Find the square root of both sides
x - 3 = +/-{{{sqrt(-4)}}}
remove the square root of -1; "i"
x - 3 = +/-{{{i*sqrt(4)}}}
x - 3 = +/- 2i
Two solutions
x = 3 + 2i
x = 3 - 2i