SOLUTION: solve the equation by completing the square, give exact solutions. x^2+ 4x-12=0

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Question 50942: solve the equation by completing the square, give exact solutions. x^2+ 4x-12=0
Found 2 solutions by darq, stanbon:
Answer by darq(90) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E2%2B+4x-12=0
the formula under is the quadratic formula:
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+

x+=+%28-4+%2B-+sqrt%28+4%5E2-4%2A-12+%29%29%2F%282%29+
x+=+%28-4+%2B-+sqrt%28+16%2B48+%29%29%2F%282%29+
x+=+%28-4+%2B-+sqrt%28+64+%29%29%2F%282%29+
x+=+%28-4+%2B-+8%29%2F%282%29+

two avaible answers;
first:
x+=+%28-4+-+8%29%2F%282%29+
x+=+-6%29+
second:
x+=+%28-4+%2B+8%29%2F%282%29+
x+=+2+

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
x^2+ 4x-12=0
x^2+4x+?=12+?
Complete the square to get:
x^2+4x+4=12+4
(x+2)^2=16
x+2=4 or x+2=-4
x=2 or x=-6
Cheers,
Stan H.