Question

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

Side 1: 5x2 + 2x - 3
Side 2: 8x - 3x2 + 2
The perimeter of the triangle is 2x3 - 5x2 + 4x - 8.

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.

Answer 1

Perimeter of a triangle (P) = A + B + C

A = 5x2 + 2x - 3
B = 8x - 3x2 + 2
C = ?
P = 2x3 - 5x2 + 4x - 8

See any way to solve this now?

Answer 2

add like terms?

Answer 3

@AkashdeepDeb

Answer 4

@triciaal

Answer 5

What is the total length of the two sides, 1 and 2, of the triangle?
add 1 and 2

Answer 6

do I add like terms

Answer 7

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

Answer 8

yes

Answer 9

P = A+ B + C
C = P - (A + B)

Find C.

Answer 10

-15x^4 + 10x^2 -5 after I add like terms right

Answer 11

(5x2 + 2x - 3) + (8x - 3x2 + 2) =(5x^2 -3x^2) +(2x + 8x) + (-3 + 2 )
do you see the like terms now?

Answer 12

yes I see them

Answer 13

all the x^2 together ; the x terms together etc

Answer 14

so for Part A write the result when you simplify each group

Answer 15

-15x^4 + 10x^2 -5 for a

Answer 16

no you do not have any terms in x^4
review the post x^2 together x together and numbers together

Answer 17

(5x^2 -3x^2) +(2x + 8x) + (-3 + 2 )
2 x^2 + 10 x -1

Answer 18

o ok ok I see

Answer 19

good we can't mix apples and oranges even though they are both fruits

Answer 20

True

Answer 21

now for part b
you have the sum of all 3 sides and you know the sum of 2 sides
to get the 3rd side do as above P - (a + b) = c where c is the 3rd side and (a + b) is the sum of the (fruit basket)

Answer 22

2x3 - 5x2 + 4x - 8 - (2 x^2 + 10 x -1) = ?

Answer 23

o ok so I then distribute it correct

Answer 24

2 x^3 - 7 x^2 + 14 x -7

Answer 25

yes and simplify by grouping like terms

Answer 26

o ok I see

Answer 27

I will be right back in just a sec

Answer 28

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

Answer 29

I am not sure how to determine if the polynomials are closed under addition and subtraction

Answer 30

its ok I believe that this is closed under addition and subtraction thank you so much for helping me in just a few minutes can you help me with another one but itll be about 15 minuets before I come back is that ok

Answer 31

post

Answer 32

ill be back in 15 mins got to eat lunch