Question

What is a closed triangle? More info below.

Answer 1

Side 1: 8x2 - 5x - 2
Side 2: 7x - x2 + 3

The perimeter of the triangle is 4x3 - 3x2 + 2x - 6.

Part A: What is the total length of the two sides, 1 and 2, of the triangle?

Part B: What is the length of the third side of the triangle?

Part C: Do the answers for Part A and Part B show that the polynomials are closed under addition and subtraction? Justify your answer.

I did parts A and B but have no idea what it means to be closed.

Answer 2

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