A system of equations is given.

y=3x+6
2x+4y=−4
What is the value of y in the system?
A
-15

B
-7

C
-2

D
0

y = 0

Step-by-step explanation:

The given system of linear equations is expressed as

y = 3x + 6

3x - y = - 6- - - - - - - - - - - - -1

2x + 4y = - 4- - - - - - - - - - - -2

We would eliminate x by multiplying equation 1 by 2 and equation 2 by 3. It becomes

6x - 2y = - 12- - - - - - - - - - -3

6x + 12y = - 12- - - - - - - - - - - -4

Subtracting equation 4 from equation 3, it becomes

- 14y = 0

y = 0

Substituting y = 0 into equation 1, it becomes

3x - 0 = - 6

3x = - 6

Dividing the left hand side and the right hand side of the equation by 3, it becomes

3x/3 = - 6/3

x = - 2