The easy thing to do is eliminate x by subtraction
x + 7y = 24
- x - 9y = -24
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16y = 48
now solve for y and then substitute the value into either original equation to find x
Yes it is a function. It passes the vertical line test. In other words, it is impossible to draw a single vertical line through more than one point on the V shaped graph. Any input leads to exactly one output.
The domain is the set of all real numbers. This is because we can plug in any x value leading to some specific y value. There are no holes or gaps or jumps to indicate we must restrict any given x value. The domain would not be the set of whole numbers only because values between the whole numbers (eg: decimal values like x = 2.75) work just fine.
The range is the set of y values such that y is either 0 or larger than 0. In short,
the range is 
. Notice how any point on the V shaped graph has a y coordinate that is either 0 or larger than 0. It is impossible to get a y value that is negative.
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In summary,
Yes it is a function
Domain: all real numbers
Range:

So
the answer is choice B
Answer:
Entrance fee should be proportional to the number of visitors -- this means that if we divide entrance fee by number of visitors for each of them, we would have the same number.
Step-by-step explanation:
Museum C
Substitute the number for the appropriate variables and solve
(ab)^2
(4×3)^2
(12)^2
12×12
144
Your answer is B.144
Perentheses, probably do multiplication.