Question

Which polynomial is factored completely?

Answer 1

Answer:

121x² + 36y²

Explanation:

The question is equivalent to, "which answer cannot be factored anymore?"

1. This is the sum of squares (11x)² +(6y)². Such a sum has no factorization in real numbers.
2. The first factor can have a factor of 4 removed: (4x+4) = 4(x+1)
3. The difference of squares can be factored: (x²-4) = (x-2)(x+2)
4. Each term has a coefficient that is a multiple of 3, so 3 can be factored out.