L. f. richardson proposed a model to describe the spread of war fever. his proposal: if y(t) is the percent of the population advocating war at time t, then the rate of change of y(t) at any time is proportional to the product of the percentage of the population advocating war and the percentage not advocating war. set up a differential equation that is satisfied by y(t). (note: use k for the constant of proportionality with k > 0.)y' = , k > 0

y'(t)=ky(t)(100-y(t))

Step-by-step explanation:

The rate of change of y(t) at any time is the derivative of y with respect to time y, y'(t)

If y(t) is the percent of the population advocating war at time t

then 100-y(t)  is the percent of the population not advocating war

The product of the percentage of the population advocating war and the percentage not advocating war would be

y(t)(100-y(t))

If the rate of change of y(t) at any time is proportional to the product of the percentage of the population advocating war and the percentage not advocating war, then

y'(t)=ky(t)(100-y(t))

where k is the constant of proportionality

connie < felicia < stew

step-by-step explanation:

stew:

we need to find the slope

m = (y2-y1)/ (x2-x1)

    = (2650-795)/(10-3)

    = 1855/7

265 words per minute

connie:

we need to find the slope

m = (y2-y1)/ (x2-x1)

we have two points (0,0) and (4,800)

m = (800-0)/(4-0)

  m = 800/4

    200 words per minute

felicia:

260 words per minute

200< 260 < 265

connie < felicia < stew

{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