2x - 4y = 12.....= x - 2y = 6
3x - 6y = 21..= x - 2y = 7
these are parallel lines with no solution
Answer: Choice C

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Explanation:
The blue portion on the left is represented by
as it describes values smaller than -2. Notice the open hole at -2 which indicates we do not include this value. So that's why we go with
instead of 
The blue portion on the right is represented as
describing values that are equal to 4, or larger than 4.
So overall, the entire graph visually represents x values such that 
Side note: the "or" means we pick one region or the other, but not both regions at the same time.
Answer:
The answer is 300
Step-by-step explanation:
His allowance is $20
He saves 20(.53)
He spends 20(.26)
He uses $2
20 - 20(.53) - 20(.26) - 2 = Money left