There are 52 contacts in your phone. The only family members' numbers you have are your dad's, mom's, and brother's. What are the odds of selecting a number in your phone that is not your family? Write your answer as 1:2 which is reduced as much as possible.

49:52

Step-by-step explanation:

Given that:

Total number of contacts on phone = 52

Family members in phone book : dad, mom, brother

Total number of family members = 3

Hence, non family members = 52 - 3 = 49

Number of family members to total phone contact

Selecting a contact that is not a family member :

49 : 52

step-by-step explanation:

de-gf

hj=3x+20

ji=15x-64

{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