Answers

2014-11-05T14:30:43+08:00
Simple math.

First of all, you need to factor the expression

4x² +12x + 9

This will be a trial and error method.

Since you have a given choice, it will be obvious to know the right answer. We are talking about squares here

So

(2x + 3)  will be the right one. Since only the 2x times itself will give us 4x^2

Remember Area of square is equal to side squared. or A = a^2

let's check:

          2x + 3
          2x + 3
-------------------
          6x + 9  -> (2x + 3) * 3
4x^2 + 6x        -> (2x + 3) * 2x
-------------------
4x^2 + 12x + 9 -> correct

I hope it helps
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