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# Confused? watch

1. Hey, so I've got a pretty basic problem off of one of my recent tests, but I'm really confused by the answer.

Develop: (x – 3)^2

I thought the answer would be x^2 - 9, but the answer is actually x^2 - 6x + 9.

Can someone explain the steps, and what I did wrong?

Thanks
2. (x - 3)^2 = (x - 3)(x - 3)

Expand the right hand side, what do you get?

And you know you must be wrong because clearly (10 - 9)^2 = (1)^2 = 1, where as you're claiming it should be 10^2 - 9^2 = 100 - 81 = 19. You can almost always check your answers to algebraic questions, so there's no excuse for getting them wrong.
3. (Original post by ec9999)
Hey, so I've got a pretty basic problem off of one of my recent tests, but I'm really confused by the answer.

Develop: (x – 3)^2

I thought the answer would be x^2 - 9, but the answer is actually x^2 - 6x + 9.

Can someone explain the steps, and what I did wrong?

Thanks
The expansion of the brackets can be done by using , however, in this case you have the strange word DEVELOP I have never seen this word in this context, so am puzzled.
4. ouch.

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Updated: January 24, 2010
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