Solve for x:
x^2 - 10 x + 36 = 0
Solve the quadratic equation by completing the square.
Subtract 36 from both sides:
x^2 - 10 x = -36
Take one half of the coefficient of x and square it, then add it to both sides.
Add 25 to both sides:
x^2 - 10 x + 25 = -11
Factor the left hand side.
Write the left-hand side as a square:
(x - 5)^2 = -11
Eliminate the exponent on the left-hand side.
Take the square root of both sides:
x - 5 = i sqrt(11) or x - 5 = -i sqrt(11)
Look at the first equation: Solve for x.
Add 5 to both sides:
x = 5 + i sqrt(11) or x - 5 = -i sqrt(11)
Look at the second equation: Solve for x.
Add 5 to both sides:
x = 5 + i sqrt(11) or x = 5 - i sqrt(11)
The answer is "C"
