Question

please help!

Answer 1

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 2

Part A
total length = 3x^2 - 4x - 1 + 4x - x^2 + 5

Answer 3

Thats the whole answer?

Answer 4

@welshfella

Answer 5

3rd side is 5x^3

Answer 6

Thank you! Can you help me with part C please!

Answer 7

sure!

Answer 8

Thank you!

Answer 9

you need to use algebraic properties
associative or commutative

Answer 10

Can you help please!

Answer 11

yeah, just a second. let me work it out. ok?

Answer 12

ok no problem :]

Answer 13

ok....see if this will help you...i had to type it in another program because it helps me with the math...

Answer 14

Side 1 = 8x² - 5x - 2
Side 2 = 7x - x² + 3
Perimeter, P = 4x³ - 3x² + 2x - 6

A. ) Length, L = Side 1 + Side 2

Subbing known values,

L = 8x² - 5x - 2 + 7x - x² + 3
L = 8x² - x² - 5x + 7x - 2 + 3
L = 7x² + 2x + 1

Total Length of Two Sides = 7x² + 2x + 1
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B.) Third Side, S = P - Side 1 - Side 2

Subbing,

S = 4x³ - 3x² + 2x - 6 - (8x² - 5x - 2) - (7x - x² + 3)
S = 4x³ - 3x² + 2x - 6 - 8x² + 5x + 2 - 7x + x² - 3
S = 4x³ - 3x² - 8x² + x² + 2x + 5x - 7x - 6 + 2 - 3
S = 4x³ - 10x² - 7

Third Side = 4x³ - 10x² - 7
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C.) Adding or subtracting the polynomials yields polynomials so they are closed under addition and subtraction.

Answer 15

Okay thank you so much!

Answer 16

wait...i might of did that wrong... wait...does your question have answers? or do you have to make them?

Answer 17

I ahve to type them.

Answer 18

oh...ok well i hope this helps...and i hope it is right...im pretty positive they are...