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Two straight-line charges are drawn on the same axes. One has a rate of change of 6 and the other has a rate of change of -9. Which line is steeper on the page?
AThe line whose rate is -9
BIt cannot be judged from rates
CNeither, both are equally steep
DThe line whose rate is 6
Answer & Solution
Correct answer: A. The line whose rate is -9
1. Steepness is judged by the size of the rate of change, ignoring whether it is positive or negative.
2. Ignoring the sign, the two sizes are 6 and 9.
3. Nine is bigger than six, so the line with rate -9 is the steeper of the two.
4. The sign only says which way the line slants: -9 slants down, 6 slants up.
5. Option D falls for the idea that a positive rate must beat a negative one, which mixes up direction with steepness.
_Source: OpenStax College Algebra (CC BY 4.0), Ch 4 "Linear Functions", section 4.1 Linear Functions_
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