SOLUTION: How to solve x^2-5x+2=0 by completing the square

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Question 878383: How to solve x^2-5x+2=0 by completing the square
Found 2 solutions by josgarithmetic, solver91311:
Answer by josgarithmetic(39630) About Me  (Show Source):
You can put this solution on YOUR website!
The missing square term is %28-5%2F2%29%5E2=25%2F4.
Add 25/4 to both sides of the equation, simplify, and then form the binomial factor, and arrange the equation into standard form.

x%5E2-5x%2B25%2F4%2B2=25%2F4
%28x-5%2F2%29%5E2=25%2F4-2
%28x-5%2F2%29%5E2=21%2F4
x-5%2F2=0%2B-+sqrt%2821%29%2F2
highlight%28x=5%2F2%2B-+sqrt%2821%29%2F2%29

Find the lesson for this.

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

I'll do you one better; here is how to solve any quadratic by completing the square:

Step 1: If there is a lead coefficient other than 1, divide both sides of the equation by the lead coefficient.

Step 2: Add the opposite of the constant term to both sides.

Step 3: Divide the first degree term coefficient by 2 then square the result.

Step 4: Add the result of step 3 to both sides of the equation.

Step 5: Factor the resulting perfect square trinomial in the Left Hand Side.

Step 6: Take the square root of both sides.

Step 7: Add the opposite of the constant term to both sides and simplify the Right Hand Side.

John

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