Question

HELP

Answer 1

The following formula models the number of prison inmates, P, in thousands, who are in U.S. prisons x years after 1980.

P = 2 x^2+24 x+318

Find the first year in which the population of U.S. prisons was approximately 638 thousand people.

Answer: The population reached 638 thousand people in the year

Answer 2

@jim_thompson5910

Answer 3

\[P(x)=2x ^{2}+24x+318\]

Answer 4

Correct?

Answer 5

Wait now,
You are looking for how much population?

Answer 6

no the year when the population was 638

Answer 7

i ment 638 thousand

Answer 8

So you know how a function works? X is the value you input (in this case years) and P(x)=population at x-years. Yes?

Answer 9

P is already in thousands

so if P = 2 for instance, then you have a population of 2,000 (not just 2)

Answer 10

\[638=2x^2+24x+302\]

Answer 11

Mertsj has the right equation because P = 638 means the population is 638,000

Answer 12

@Mertsj, thats correct.

Answer 13

so x=-20 and x=8

Answer 14

wait chck this before you stated this was the first equation
P(x)=2x2+24x+318
but you said you wrote it like this
638=2x^2+24x+302
is it 318 or 302

Answer 15

+318

Answer 16

matlee has a good point that I didn't notice

Answer 17

thnx jim ok so would the answer still be right?

Answer 18

which answer are you referring to?

Answer 19

x=-20 x=8

Answer 20

Sorry guys keep losing connections is that happening to anyone else

Answer 21

then you ignore the negative answers because x is the number of years after 1980

Answer 22

ok nevermind it went through

Answer 23

yeah the site is weird sometimes

Answer 24

so the only answer is x = 8

Answer 25

but it says in what year is 8 a year?

Answer 26

so whats the final answer?

Answer 27

x = 8 is the number of years after 1980

so you simply add 8 to 1980 to get 1988

Answer 28

your a genious