AlgebraMediumSlope from the two intercepts
Algebra practice question
A line in the xy-plane has an x-intercept of 4 and a y-intercept of −6. What is the slope of the line?
- A. 3/2Correct
- B. −3/2
- C. 2/3
- D. −2/3
Answer: A. 3/2
The intercepts are the points (4, 0) and (0, −6). Slope = (−6 − 0)/(0 − 4) = (−6)/(−4) = 3/2.
Why the other answers are wrong
- B. −3/2
- The sign is wrong: rising from (0, −6) to (4, 0), the line goes UP as x increases, so the slope is positive.
- C. 2/3
- 2/3 is run over rise. Slope is rise over run: 6/4 = 3/2.
- D. −2/3
- −2/3 has both the ratio inverted and the wrong sign.
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