4x - 2y =7
X + 2y =3
What are x and y ??

4x - 2y = 7

x + 2y =  3

5x = 10

x=2 and y=0

{x,y} = {2,1/2}

Step-by-step explanation:

Solve by Substitution :

1. Solve equation [2] for the variable  x  

 [2]    x = -2y + 3

2. Plug this in for variable  x  in equation [1]

  [1]    4•(-2y+3) - 2y = 7

  [1]     - 10y = -5

3.Solve equation [1] for the variable  y  

  [1]    10y = 5

  [1]    y = 1/2

By now we know this much :

   x = -2y+3

   y = 1/2

4.Use the  y  value to solve for  x  

   x = -2(1/2)+3 = 2

Solution :

{x,y} = {2,1/2}

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