Hello from MrBillDoesMath!
Answer:
x = -11, y = 6
Discussion:
I don't understand the answer shown -- "Doesn't Exist" -- especially as part of the problem statement is not displayed, BUT
-6x + 3y = 84 => divide both sides by 3
-2x + y = 84/3= 28
-2x + y = 28 (A)
Multiply X = -23 + 2Y by 2 to get
2x = - 46 + 4y (B)
Adding (A) and (B) gives
(-2x + y ) + (2x) = 28 + (-46 + 4y) =>
y = 28 -46 + 4y => as -2x + 2x = 0
y = -18 + 4y =>
18 = 3y =>
y = 6
From (A) -2x + (6) = 28 or -2x = 28 -6 = 22 so x = -11
Thank you,
MrB