1. The user mentioned "perpendicular nhi dia hai," which means "perpendicular is not given." 2. In geometry and algebra, when two lines are perpendicular, their slopes satisfy the condition $m_1 \times m_2 = -1$. 3. If the problem involves finding a line perpendicular to another, you need to use this slope relationship. 4. Without the perpendicular condition, you cannot apply this rule. 5. Please provide the full problem or clarify what you need help with regarding perpendicular lines.