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Two straight-line charges are compared on the same axes to see where one becomes better value. How many points can the two lines have in common?
AOnly one, since two lines always cross once
BTwo at most, where the lines cross twice
CNone, unless the rates are both positive
DOne, none, or every point along the line
Answer & Solution
Correct answer: D. One, none, or every point along the line
1. Two straight lines with different rates of change cross at exactly one point.
2. Two lines with the same rate but different starting values never meet at all.
3. Two rules that turn out to describe the very same line share every point on it.
4. So there are three possible answers, not one, which rules out option A.
5. Straight lines cannot bend back, so they never cross twice, ruling out option B.
_Source: OpenStax College Algebra (CC BY 4.0), Ch 4 "Linear Functions", section 4.2 Modeling with Linear Functions_
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