SOLUTION: Solve and show steps by completing the square: x^2+8x+13=0

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Question 184184: Solve and show steps by completing the square:
x^2+8x+13=0

Found 2 solutions by jim_thompson5910, solver91311:
Answer by jim_thompson5910(35256)   (Show Source): You can put this solution on YOUR website!

Start with the given expression.


Take half of the coefficient to get . In other words, .


Now square to get . In other words,


Now add and subtract . Make sure to place this after the "x" term. Notice how . So the expression is not changed.


Group the first three terms.


Factor to get .


Combine like terms.


So after completing the square, transforms to . So .


So is equivalent to .


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Now let's solve


Start with the given equation.


Add to both sides.


Combine like terms.


Take the square root of both sides.


or Break up the "plus/minus" to form two equations.


or Simplify the square root.


or Subtract from both sides.


=====================================================


Answer:


So the solutions are or .

Answer by solver91311(24713)   (Show Source): You can put this solution on YOUR website!




Move the constant term to the right side:



Divide the coefficient on the x term by 2 and square the result. Add this result to both sides. 8 divided by 2 is 4 squared is 16:



You now have a perfect square on the left, factor it:



Take the square root of both sides, remembering to consider both the positive and negative root:



Solve for x:



John


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