Answer:
Solve for x over the real numbers:
x^2 - 12 x - 4 = 0
Add 4 to both sides:
x^2 - 12 x = 4
Add 36 to both sides:
x^2 - 12 x + 36 = 40
Write the left hand side as a square:
(x - 6)^2 = 40
Take the square root of both sides:
x - 6 = 2 sqrt(10) or x - 6 = -2 sqrt(10)
Add 6 to both sides:
x = 6 + 2 sqrt(10) or x - 6 = -2 sqrt(10)
Add 6 to both sides:
Answer: |
| x = 6 + 2 sqrt(10) or x = 6 - 2 sqrt(10)
