Answer:
C. x + 2y = 10
-4x - y = 2
Step-by-step explanation:
A. quickest way is to plug in -2, 6 and see which one works
B. this is the other way
1. x + 2y = 10
-4x - y = 2
2. multiply 4 with x + 2y = 10 so i can get 4x + 8y = 40
i want +4x so i can cancel with the -4x in -4x - y = 2
3.
4x + 8y = 40
-4x - y = 2
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7y = 42
y = 6
4. then plug in 6 into an equation to get x
-4x - y = 2
-4x -6 = 2
-4x = 8
x = -2
