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Two tariffs are drawn on the same axes. They never meet, however far the lines are extended in either direction. What must be true of them?
AOne rate is double the other rate
BThey share the same starting amount
CTheir rates of change multiply to 1
DThey share the same rate of change
Answer & Solution
Correct answer: D. They share the same rate of change
1. Lines that never meet are parallel.
2. Parallel lines rise or fall at exactly the same steepness, so their rates of change match.
3. Their starting amounts must differ, or the two lines would sit on top of each other.
4. Option B says the opposite of that, so it cannot be right.
_Source: OpenStax College Algebra (CC BY 4.0), Ch 4 "Linear Functions", section 4.1 Linear Functions_
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