The answer is 15 i think i don't know
<h2>Given :</h2>
<h2>Solution : </h2>

Through the statement above we have,
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You have a lot of questions here, I can help you with a few of them.
When you simplify the polynomials, you put together all of the terms that have the same degree. That means the variables have the same exponents. The number of terms are the items separated by plus and minus signs.
Here are the answers for the first three:
1)

2)

3)
(x-5)^2 . ( x+5)
=( x^2 - 10x + 25) . ( x+ 5)
=x^3 + 5x^2 - 10x^2 -50x + 25x + 125
= x^3 - 5x^2 -25x +125
32,64,128
Hope i helped :)