Answer: Choice C
x+y = 28
3x+4y = 100
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Explanation:
x and y are placeholders for nonnegative whole numbers.
Specifically,
x = number of three point questions
y = number of four point questions
Since we have 28 questions total, this must mean x+y = 28. That forms the first equation in our system of equations.
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Now let's form the second equation:
x = number of three point questions
3x = points we get from all the three point questions
y = number of four point questions
4y = points we get from all the four point questions
3x+4y = all points possible
3x+4y = 100 is the second equation
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So we have this system
[tex]\begin{cases}x+y = 28\\3x+4y = 100\end{cases}[/tex]
which fits the conditions in the instructions.
