SOLUTION: Solve x^2 – 4x = 14

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Question 694339: Solve x^2 – 4x = 14
Answer by BigToosie(32) About Me  (Show Source):
You can put this solution on YOUR website!
x^2 - 4x = 14
Step 1: Subtract 14 on both sides of the the equation to set the equation = to 0
x^2 - 4x - 14 = 0
Step 2: Use quadratic formula to solve the equation
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
where a = 1, b = -4, c = -14
x = (-(-4)+- sqrt(b^2-4ac))/2a
x = 4 +- sqrt(-4^2-4(1)(-14))/2(1)
x = 4 +- sqrt(16+56)/2
x = 4 +- sqrt(72)/2
x = 4 +- (6 sqrt 2) /2
= 4/2 + (6 sqrt 2)/2
= 2 + 3 sqrt 2

x = 4 - (6 sqrt 2) /2
= 4/2 - (6 sqrt 2)/2
= 2 - 3 sqrt 2