Solve this equation by completing the square.

3x2 - 4x = -2

Question

Solve this equation by completing the square.

3x2 - 4x = -2

anonymous · Answer

@CliffSedge ... can you help?  I have to sign off...  thanks!

anonymous · Answer

Factor out the 3 to make the left side
x^2-4x/3 to start.

anonymous · Answer

Then find half of -4/3, square it, multiply it by 3 and add it to both sides.
3(x^2-4x/3) + ___ = -2 + ___

anonymous · Answer

i don't know i have no idea

anonymous · Answer

You don't know how to square a fraction? Or you don't know how I got to this step?

anonymous · Answer

yeah i dont know how i got this step

anonymous · Answer

-8/3

anonymous · Answer

Alright, let's back up and look at what we're starting with.
$$\large 3x^2-4x=-2$$
There are a couple ways to complete the square, but I prefer to have the leading coefficient be 1, so I'm going to divide everything by 3.
$$\large \rightarrow x^2-\frac{4}{3}x=-\frac{2}{3}$$

anonymous · Answer

for the blank i have -8/3

anonymous · Answer

3(x^2-4x/3) +-8/3= -2 + /8/3 its right

anonymous · Answer

Before we go on, a little background concept on what 'completing the square' means.
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