Answer: 1/(2lm).
- A 1/(2lm)
- B 1/(lm)
- C lm/2
- D l+m
Correct answer: A. 1/(2lm)
Explanation: Line lx+my=1 meets x-axis at (1/l, 0) and y-axis at (0, 1/m). Triangle with right angle at origin. Area=(1/2)×base×height=(1/2)×(1/l)×(1/m)=1/(2lm). Ans: 1/(2lm).
The slope of a line is the ratio of vertical change (rise) to horizontal change (run) between any two points on it - equivalently, the tangent of the angle θ the line makes with the positive x-axis.