Respuesta :
Answer:
A) [tex]2x^2+4[/tex]
B) [tex]5x^3-4x^2+3x-12[/tex]
C) Yes
Step-by-step explanation:
Perimeter: the distance all the way around the outside of a 2D figure.
Therefore, to calculate the perimeter, add up the lengths of all the sides.
Given expressions:
- Triangle side 1: [tex]3x^2-4x-1[/tex]
- Triangle side 2: [tex]4x-x^2+5[/tex]
- Perimeter: [tex]5x^3-2x^2+3x-8[/tex]
Part A
[tex]\begin{aligned}\sf side\:1+side\:2 & =(3x^2-4x-1)+(4x-x^2+5)\\ & =3x^2-4x-1+4x-x^2+5\\ & =3x^2-x^2-4x+4x-1+5\\ & =2x^2+4\end{aligned}[/tex]
Part B
[tex]\begin{aligned}\sf side\:3 & =\sf perimeter-(side\:1+side\:2)\\ & =(5x^3-2x^2+3x-8)-(2x^2+4)\\& = 5x^3-2x^2+3x-8-2x^2-4\\& = 5x^3-2x^2-2x^2+3x-8-4\\ & = 5x^3-4x^2+3x-12\end{aligned}[/tex]
Part C
Polynomials and closure: Polynomials will be closed under an operation if the operation produces another polynomial.
So as the addition and subtraction of the given polynomials has produced another polynomial, then the polynomials are closed under addition and subtraction.