A) 10y+(y-7)(y-5)+4y^2 (note that the little carrot -shift 6- means raised to the power of)

First we take care of the parentheses.
So, (y-7)*(y-5)= y^2-12y+35 Since I have no knowledge of what you do and do not know, I will explain this. The method is called FOIL. (acronym for first outside inside last) you take the first term in both factors, y and y, and multiply them together. So that's y^2. Then you take the outside terms of each. y and -5, and multiply them together. So far we have y^2-5y. Then we take the inside terms, -7 and y, and multiply them together. That gives us -7y. So now we have y^2-5y-7y. Then we take the last term in each factor and multiply them. -5 and -7. That gives us +35. So we combine like terms and it comes out to y^2-12y+35.

So the full equation now looks like this: 10y+y^2-12y+35+4y^2. So now it's just a matter of combining like terms.

4y^2 and y^2 add up to 5y^2. 10y and -12y add up to -2y. And 35 has no like term.

This sets your equation up as 5y^2-2y+35. This answer cannot be factored, so I'm pretty sure you can leave it as is.

I'd help with B and C, but I have my own homework to attend to. Sorry.

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