Help me understand this and how to do it?

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Simplify the following expression.
2x - 8y + 3x^2 + 7y - 12x.

3x^2 - 14x - y

3x^2 - 10x - y

3x^2 - 10x - 15y

3x^2 + 10x - y

Question

Help me understand this and how to do it?

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Simplify the following expression.
2x - 8y + 3x^2 + 7y - 12x.

3x^2 - 14x - y

3x^2 - 10x - y

3x^2 - 10x - 15y

3x^2 + 10x - y

anonymous · Answer

You need to start by combining like terms.

paki · Answer

3x^2-10x-y

anonymous · Answer

^^ That is correct.

kmullis6 · Answer

@meshlogic @paki how did you get it tho? that's what i don't understand.

paki · Answer

just combine the like terms...

anonymous · Answer

Step 1: Rearrange your equation so like-terms (same variable) are next to each other.

$$2x - 8y + 3x^2 + 7y - 12x \rightarrow 3x^2 + 2x - 12x + 7y - 8y$$

anonymous · Answer

Step 2: Combine like terms.
$$3x^2+2x−12x+7y−8y \rightarrow 3x^2-10-y$$

paki · Answer

@kmullis6  hope it clears now...as meshlogic has done :-)

kmullis6 · Answer

I'm sorry, I'm terrible at algebra.. Why was the 3x^2 put first? I know cause of the x, but why not the 2x? /:

kmullis6 · Answer

@meshlogic @paki

paki · Answer

it is at first because it carries high power i:e, 2... and also there is no matching word of this term, so it is alone :-)

anonymous · Answer

It is convention to put the highest power first; you see this in all your math texts, so just do it. :)

kmullis6 · Answer

@paki @meshlogic ok thanks i get it now :)

anonymous · Answer

Great :D

paki · Answer

pleasure