SOLUTION: if 3x squared - 2x + 7 = 0 then (x - 1/3) squared = ? i no its a fraction, i think its a positive fraction with a denomater of 9. it might be 20/9. but im not really sure....

Question 375574: if 3x squared - 2x + 7 = 0 then (x - 1/3) squared = ?
i no its a fraction, i think its a positive fraction with a denomater of 9. it might be 20/9.
but im not really sure....
Answer by jim_thompson5910(35256) (Show Source): You can put this solution on YOUR website!
First, let's complete the square.

Start with the given expression.

Factor out the coefficient . This step is very important: the coefficient must be equal to 1.

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

Now square to get . In other words,

Now add and subtract inside the parenthesis. 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.

Distribute.

Multiply.

So after completing the square, transforms to . So .

So is equivalent to .

Now let's solve for

Start with the given equation.

Subtract from both sides.

Multiply both sides by .

Multiply

So the solution is

So you were close. You were just off by a sign.

If you need more help, email me at jim_thompson5910@hotmail.com

Also, feel free to check out my tutoring website

Jim
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