Question

A tool box has a volume of x3 + 8x2 + 11x – 20 cm3 and the height is x + 5 cm. Find the polynomial that would represent the area of the bottom of the tool box? Explain your reasoning.

Answer 1

your real job is to divide
\[\frac{x^3+8x^2+11x-20}{x+5}\] i would use synthetic division,but you can do it with long division

Answer 2

you will get
\[x^2+3x-4\] do you need the steps?

Answer 3

Yes please

Answer 4

do you know how to use synthetic division?

Answer 5

synthetic division may be easier, but i think it's bad for the environment :)

Answer 6

it is a better environment for synthetic than long division. i can write the process but if you don't know it you will not understand it

Answer 7

No, can you show me how you would do it?

Answer 8

list the coefficients of
\[x^3+8x^2+11x-20\] they are


1 8 11 -20

Answer 9

because you are dividing by x + 5 put -5 on the side

1 8 11 -20

-5
_______________________________

Answer 10

bring down the 1
1 8 11 -20

-5
_______________________________
1

Answer 11

1*-5=-5
1 8 11 -20

-5 -5
_______________________________
1

Answer 12

8 - 5 = 3

1 8 11 -20

-5 -5
_______________________________
1 3

Answer 13

3*-5=-15
1 8 11 -20

-5 -5 -15
_______________________________
1 3

Answer 14

11 - 15 = -4
1 8 11 -20

-5 -5 -15
_______________________________
1 3 -4

Answer 15

-5 * -4 = 20
1 8 11 -20

-5 -5 -15 20
_______________________________
1 3 -4

Answer 16

-20 + 20 = 0
1 8 11 -20

-5 -5 -15 20
_______________________________
1 3 -4 0

Answer 17

your solution is the bottom row. it is
\[x^2+3x-4\]

Answer 18

so what hapened to the last part? explain ur reasoning?