Not 100% sure but I think it’s b. hope this helps!
Answer:
it should be : x²= 15²+8²
x²= 225+64
x²=289
x=√289
x=17
<h3>
Answer: (x-2)(x-2)</h3>
This is the same as 
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Explanation:
The middle coefficient is -4 and the last term is 4.
We need to find factors of the last term that add to the middle coefficient.
Here is a list of all ways to multiply two integers to get 4, and the sum of each pair of factors.
- -1 + (-4) = -5
- -2 + (-2) = -4
- 2 + 2 = 4
- 1 + 4 = 5
The second row of that list above is what we're after. So
-2 + (-2) = -4
-2 * (-2) = 4
Meaning the factorization is (x-2)(x-2). Note the "-2" values in each factor
We can use the FOIL rule or distribution to go from (x-2)(x-2) back to x^2-4x+4 to confirm the answer.