Question

can someone please check my answers

1. Suppose that the amount of algae in a pond doubles every 4 hours. If the pond initially contains 90 pounds of algae, how much algae will be in the pond after 12 hours?
720 pounds (my answer)
360 pounds
1440 pounds
114 pounds
2. What is the order of the numbers from least to greatest?
a= 1.5x10^3 b=1.4x10-1 c=2x10^3 d=1.4x10-2
d 10 years ago

Answer 1

\[90\times 2^3\]

Answer 2

so yeah 720

Answer 3

i have a couple more if you dont mind it will take me a minute to type them out thank you

Answer 4

3.Dorothy has decided to raise rabbits but has been warned that the number of rabbits she will have will grow very quickly. Dorothy started out with 20 rabbits and the function y=20x2.3x models the number of rabbits she will have after x months which graph represents this function? im not sure on this one
4.multiple give your answer in standard form
(3n2+2n+4)(2n-1)
6n^3+n^2+6n-4(my answer)
6n^3+7n^2+6n-4
6n^3-n^2+10n-4
6n^3+n^2+10n-4
5. multiply. (4x+3)(4x-3)
16x^2-24x-9
16x^2+24x+9
16x^2-9(my answer)
16x^2+9
6.the area of a rectangular painting is given by the trinomial x^2+2x-15. What are the possible dimensions of the painting?use factoring.
(x+5) and (x-3)(my answer)
(x+5) and (x+3)
(x-5) and (x-3)
(x-5) and (x-3)

Answer 5

can you give an explanation for 5 and 6?

Answer 6

(3n2+2n+4)(2n-1)

3n2(2n-1) +2n(2n-1) +4(2n-1)

6n^3 -3n^2 +4n^2 -2n +8n -4
1n^2 6n


4 is fine

Answer 7

i mutliplies both 4x's and got 16x^2and then multiplied 3 and -3 and got -9 so that would be 16x^2-9 for 5

Answer 8

for 6 im not totally understanding i made a logical guess if you understand it could you explain it to me

Answer 9

well thats not the reason for 5, its a shortcut based on the TYPE it is .... the product of conjugates has no term of degree 1

(a+b)(a-b)

a(a-b)+b(a-b)

aa -ba +ba -bb

aa +0 -bb

Answer 10

on 6 we need a -15 on the end, that requires opposite signage.

the only one with different signs is A

Answer 11

can you explain hot to do 5 please so far im not understanding any of theses questions and the ones i think i understand are totally wrong

Answer 12

Dorothy has decided to raise rabbits but has been warned that the number of rabbits she will have will grow very quickly.

Dorothy started out with 20 rabbits and the function y=20x2.3x models the number of rabbits she will have after x months which graph represents this function?

THis is not only unreadable, it has no graphs to pick from.

Answer 13

i just explained 5

Answer 14

if you know how to distribute (or FOIL) then you can come to the solution for 5

Answer 15

ok thanks i didnt see it

Answer 16

i didnt think of using foil but now it makes sense

Answer 17

what is the answer at number 2? i have no idea for number 2 @amistre64