Question

The lengths of two sides of a triangle are shown below:

Side 1: 3x2 - 4x - 1
Side 2: 4x - x2 + 5

The perimeter of the triangle is 5x3 - 2x2 + 3x - 8.

Part A: What is the total length of the two sides, 1 and 2, of the triangle? (4 points)

Part B: What is the length of the third side of the triangle? (4 points)

Part C: Do the answers for Part A and Part B show that the polynomials are closed under addition and subtraction? Justify your answer. (2 points)

Answer 1

A) Add 3x2 - 4x - 1 and 4x - x2 + 5
Combine like terms and simplify.

Answer 2

Part B: 5x^{3}-4x^{2}+3x-4

Answer 3

How do I add like terms, I am lost

Answer 4

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

Answer 5

Like terms are the numbers and variables that match. Such as 3x and 4x are like terms, so are -1 and 5.