The problem states that a line $l$ has a slope $m = -\frac{2}{3}$. We are asked to find the slope of a line that is perpendicular to $l$.
2025/4/22
1. Problem Description
The problem states that a line has a slope . We are asked to find the slope of a line that is perpendicular to .
2. Solution Steps
If two lines are perpendicular, the product of their slopes is .
Let be the slope of line and be the slope of a line perpendicular to .
Then .
We are given that . So,
3. Final Answer
The slope of a line perpendicular to is . The answer is b).