D would equal to either 9 or －9
9514 1404 393
Explanation:
A)
Let t and f represent the numbers of two-point and four-point questions, respectively.
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B) The number of points for each type of question is the product of the point-value per question and the number of questions of that type.
2t + 4f = 100 . . . . . the test is worth 100 points
t + f = 40 . . . . . . . . there are 40 questions on the test
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<em>Additional comment</em>
The test will have 30 two-point questions and 10 four-point questions.
The midpoint is (0,2)
Hope this helps! (:
