AlgebraMediumEquation from a slope and a point
Algebra practice question
In the xy-plane, a line with slope 1/2 passes through the point (−2, 3). Which equation represents the line?
- A. y = (1/2)x + 4Correct
- B. y = (1/2)x + 2
- C. y = 2x + 7
- D. y = (1/2)x − 4
Answer: A. y = (1/2)x + 4
3 = (1/2)(−2) + b gives b = 4.
Why the other answers are wrong
- B. y = (1/2)x + 2
- This gives y = 1 at x = −2.
- C. y = 2x + 7
- The slope is 1/2, not 2.
- D. y = (1/2)x − 4
- This gives y = −5 at x = −2.
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