X + y = -2
-3x + y = -6
solve using substitution

(1, - 3 )

Step-by-step explanation:

Given the 2 equations

x + y = - 2 → (1)

- 3x + y = - 6 → (2)

Rearrange (2) expressing y in terms of x by adding 3x to both sides

y = - 6 + 3x → (3)

Substitute y = - 6 + 3x into (1)

x - 6 + 3x = - 2

4x - 6 = - 2 ( add 6 to both sides )

4x = 4 ( divide both sides by 4 )

x = 1

Substitute x = 1 into (3) for corresponding value of y

y = - 6 + 3(1) = - 6 + 3 = - 3

solution is (1, - 3 )

a 4/6 = 9/12   not proportional

step-by-step explanation:

to find which are not proportional, we can use cross products

if it is true, they are proportional.   if it is not true, they are not proportional.

a 4/6 = 9/12

4* 12 = 6*9

48 = 54

not this is not proportional  

b 2/3 = 12/18  

2* 18 = 3 * 12

36 = 36

this is proportional

c 5/4 = 10/8  

5*8 = 4*10

40 = 40

this is proportional

d 7/5 = 35/25

7*25 = 5 * 35

175 = 175

is proportional