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When graphing a line by plotting points, why is it a good habit to use three points instead of just two?
AA wrong pair still draws a line, but a third point exposes the error
BTwo points are mathematically impossible to draw a line through
CThree points always form a perfectly straight line by definition
DThe equation itself requires exactly three unique solutions
Answer & Solution
Correct answer: A. A wrong pair still draws a line, but a third point exposes the error
1. It only takes two points to determine a line, but if one of those two is wrong, the two points still draw some line, just the wrong one.
2. Using three points means that if one point is incorrect, it will not line up with the other two, revealing the mistake.
3. Lines are not limited to exactly three solutions, and two correct points are perfectly capable of determining a line.
_Source: OpenStax Elementary Algebra (CC BY 4.0), Ch 4 "Graphs", section 4.2 Graph Linear Equations in Two Variables_
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