Solve the system using elimination.
3x - y = 28
3x + y = 14
(8, -4)
(-4,8)
(7,-7)
(-7,7)

x = 7 , y = -7

Step-by-step explanation:

Solve the following system:

{3 x - y = 28 | (equation 1)

3 x + y = 14 | (equation 2)

Subtract equation 1 from equation 2:

{3 x - y = 28 | (equation 1)

0 x+2 y = -14 | (equation 2)

Divide equation 2 by 2:

{3 x - y = 28 | (equation 1)

0 x+y = -7 | (equation 2)

Add equation 2 to equation 1:

{3 x+0 y = 21 | (equation 1)

0 x+y = -7 | (equation 2)

Divide equation 1 by 3:

{x+0 y = 7 | (equation 1)

0 x+y = -7 | (equation 2)

Collect results:

 {x = 7 , y = -7

step-by-step explanation:

to find if any function is an inverse of the other, put the first equation in as x in the next one. then simplify and solve. if at the end you get the statement y = x, then it is an inverse. if you get anything else, it is not.

step-by-step explanation:

i found the life tables for the year 2012. 

life table of males at age 30. probability of dying between ages x and x+1

total population:  

29–30 . . . . . . . . . . . . 0.001030

30–31 . . . . . . . . . . . . 0.001061

males:  

29–30 . . . . . . . . . . . . 0.001420

30–31 . . . . . . . . . . . . 0.001448

white population

29–30 . . . . . . . . . . . . 0.001005

30–31 . . . . . . . . . . . . 0.001037

white males

29–30 . . . . . . . . . . . . 0.001372

30–31 . . . . . . . . . . . . 0.001399

non hispanic white population

29–30 . . . . . . . . . . . . 0.001083

30–31 . . . . . . . . . . . . 0.001116

non hispanic white males

29–30 . . . . . . . . . . . . 0.001477

30–31 . . . . . . . . . . . . 0.001503

jacob, non hispanic white male. 30 years old.

probability that jacob lives to be 30 years old. 

since the given probabilities are probabilities of dying, i think we simply subtract it from 1 to get the probability of living. we will use the probability of non hispanic white male.

                                          probability of living to be 30 y.o.

29 - 30 : 1 - 0.001477 = 0.998523

30 - 31 : 1 - 0.001503 = 0.998497