AlgebraMediumParameter that appears twice in a line's equation
Algebra practice question
In the xy-plane, the line y = ax + a passes through the point (3, 8), where a is a constant. What is the value of a?
Answer: 2
8 = 3a + a = 4a → a = 2.
Common wrong answers
- If you answered 4
- 4 is the coefficient 4 in 4a = 8, not a itself.
- If you answered 5
- 5 comes from 8 − 3, subtracting instead of dividing.
- If you answered 8/3
- 8/3 comes from 8 = 3a, ignoring the second a.
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