Are the lines \(3x-4y=12\) and \(4x+3y=7\) perpendicular?
Yes
No
Only if they intersect at the y-axis
Cannot be determined
Correct answer: Yes
Solution
For \(3x-4y=12\), slope \(m_1=\frac{3}{4}\). For \(4x+3y=7\), slope \(m_2=-\frac{4}{3}\). Since \(m_1m_2=\frac{3}{4}\cdot\left(-\frac{4}{3}\right)=-1\), the lines are perpendicular.