Completing the square using algebra tiles

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Gitty
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I'm trying to create a square using algebra tiles. The question is x^2 + 4x + 5. I know how to do it without the algebra tiles but I don't know how to do it with the algebra tiles.

Can anyone give me a hand with this?
 
Consider the following diagram:

View attachment 5305

In the quadratic:

$$y=x^2+4x+5$$

Let the green square represent $x^2$, which we have, and the 2 blue rectangles each represent $$2x$$ ($x$ by 2), which we also have, and so we see the red square will need to have side lengths of 2, and thus an area of 4, so we can then write:

$$y=\left(x^2+4x+4\right)+1$$

We know the expression within the parentheses represents the entire square, whose sides measure $x+2$, and so we may write:

$$y=(x+2)^2+1$$
 
Attachments
  • Square tile diagram for completing the square: a large green square labelled x on top and x on the left, with a blue strip labelled b/2a along the right and bottom edges and a small red square in the bottom-right corner.
    comsquare.jpg
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