x = 0, and y = -4
6x - 7y = 28 ................................. equation 1
2x + 4y = -16.................................. equation 2
so we need to eliminate one of the variable before i can get the other variable
so let eliminate x first
to eliminate x we need to make the coefficient of x in both equations equal
so, to do that we need to multiply equation 1 by 1 and multiply equation 2 by 3
6x - 7y = 28 multiply by 1
2x + 4y = -16 multiply by 3
6x*1 - 7y*1 = 28*1
2x*3 + 4y*3 = -16*3
6x - 7y = 28 ..................... equation 3
6x + 12y = -48 ........................equation 4
so, we can solve equation 3 and 4 simultaneously
to eliminate x we will substract equation 4 from 3
6x - 7y = 28
-
6x + 12y = -48
6x - 6x = 0
-7y - (12y) = -19y
28 - (-48) = 76
we have successfully eliminate x
we have, -19y = 76
-19y = 76
dividing both sides by -19
-19y/19 = 76/-19
y = -4
To solve for x we can put y= -4 in either equation 1 or equation 2
so let us try equation 2, then you will try equation 1
equation 2 is 2x + 4y = -16
since y= -4
2x + 4(-4) = -16
2x -16 = -16
2x = -16 +16
2x = 0
x = 0/2
x = 0