A nature conservation organization tracks the population of an endangered species of foxes over time. The population number is modeled by the function (x)=−1.20.7x+10,000(x)=−1.20.7x+10, 000, where xx is time in years since the organization began tracking the foxes. Calculate the average rate of change for the population over the following intervals: [0,10][0,10], [20,30][20,30], [40,50][40,50], [60,70][60,70]. Part A: Over which time interval did the population decline the fastest? Part B: Over which time interval did the population decline the slowest? Select one answer for Part A and one answer for Part B.

{x = -1/2 ,   y = -1

step-by-step explanation:

solve the following system:

{2 x + y = -2

{10 x - 3 y = -2

in the first equation, look to solve for y:

{2 x + y = -2

{10 x - 3 y = -2

subtract 2 x from both sides:

{y = -2 x - 2

{10 x - 3 y = -2

substitute y = -2 x - 2 into the second equation:

{y = -2 x - 2

{10 x - 3 (-2 x - 2) = -2

10 x - 3 (-2 x - 2) = (6 x + 6) + 10 x = 16 x + 6:

{y = -2 x - 2

{16 x + 6 = -2

in the second equation, look to solve for x:

{y = -2 x - 2

{16 x + 6 = -2

subtract 6 from both sides:

{y = -2 x - 2

{16 x = -8

divide both sides by 16:

{y = -2 x - 2

{x = -1/2

substitute x = -1/2 into the first equation:

{y = -1

{x = -1/2

collect results in alphabetical order:

answer:   {x = -1/2 ,   y = -1

answer: none of these answers are correct only the second half is

step-by-step explanation: