Difficulty: Easy
Correct Answer: y = 4x
Explanation:
Introduction / Context:
This concept check asks you to match a verbal line description to its algebraic form. “Ordinate” means y-coordinate and “abscissa” means x-coordinate. Saying “the ordinate is four times the abscissa” translates directly to y = 4x for every point on the line.
Given Data / Assumptions:
Concept / Approach:
Translate words to symbols. “y is four times x” → y = 4x. Check each option by rearranging to an explicit y = mx form where possible, and compare the slope and proportionality to 4.
Step-by-Step Solution:
Verification / Alternative check:
Pick x = 2. Then y must be 8. Only y = 4x passes the test exactly for all x.
Why Other Options Are Wrong:
They represent lines with slopes −4, 1/4, or −1/4, none of which encode y being four times x.
Common Pitfalls:
Confusing “four times” (multiply by 4) with “one fourth” (divide by 4), or missing the negative sign when moving terms across the equals sign.
Final Answer:
y = 4x
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