Questions on Algebra: Quadratic Equation answered by real tutors!

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Question 153089: Solve for x
x^2+72=12x: Solve for x
x^2+72=12x
Answer by Earlsdon(3716) About Me  (Show Source):
You can put this solution on YOUR website!
Solve for x:
x^2+72 = 12x First, subtract 12x from both sides.
x^2-12x+72 = 0 The trinomial is not factorable, so use the quadratic formula: x = (-b+-sqrt(b^-4ac))/2a, where a = 1, b = -12, and c = 72.
x = (-(-12)+-sqrt((-12)^2-4(1)(72)))/2(1)
x = (12+-sqrt(144-288))/2
x = (12+-sqrt(-144))/2
x = (12+-12sqrt(-1))/2
x = 6+6i or x = 6-6i