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Completing the square?

Simplify (x+4)(x+2) - 2(x+2), and explain why the expression can never be negative, whatever the value of x.

I have expanded the brackets to give me:
x^2 + 4x + 4

And then I completed the square to give me:
(x+2)^2

I don’t know what to do next. Thank you.
When you square a number, the result cannot has to be greater than or equal to zero. That's pretty much it.
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Sasuto
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Original post by Itsmikeysfault
When you square a number, the result cannot has to be greater than or equal to zero. That's pretty much it.

Oh it was that simple??? Thanks :h:
Original post by Sasuto
Oh it was that simple??? Thanks :h:


It really is, because you made it so: you have converted it to a square term and no matter how long this term in brackets is, no matter if you add or subtract the numbers in the square term, it is always positive. Square terms can't be negative as result. In this sense: well done! :smile:
(edited 2 years ago)

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