SOLUTION: Solve this equation by completing the square: 5x^2-20x+6=0

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Question 875758: Solve this equation by completing the square: 5x^2-20x+6=0
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
Add and subtract the term, cross%28%28-20%2F2%29%5E2=100%29(See solution below). Identify the proper factorable trinomial, simplify forming the square; and then the solution process for x should be uncomplicated.

Study this lesson: Completing the Square to Solve General Quadratic Equation

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Possible mistake in your answer key. This here may help:

5%28x%5E2-4x%29=-6
The term to add to both sides would be %28-4%2F2%29%5E2=4.
5%28x%5E2-4x%2B4%29=-6%2B5%2A4
Inside the parentheses was added 4, but we add then 5*4 to the right side, because we must account for the factorized 5 on the left side.
5%28x-2%29%5E2=20-6
5%28x-2%29%5E2=14
%28x-2%29%5E2=14%2F5
x-2=0%2B-+sqrt%2814%2F5%29
x-2=0%2B-+sqrt%2814%2F5%29sqrt%285%2F5%29
x-2=0%2B-+sqrt%2870%29%2F5
highlight%28x=2%2B-+sqrt%2870%29%2F5%29

Note that if we started with the 6 still on the left side and had the original expression still equal zero, we would want to add and subtract just on the left side.