The line \(r\) passes through the points \((-4,4)\) and \((5,10)\) and the line \(s\) passes through the points \((-10,9)\) and \((-4,0)\). Is the line \(r\) perpendicular to \(s\)?
 
Answer:
 
Let \(m_1\) be the slope of the line '\(r\)', and \(m_2\) be the slope of the line '\(s\)'.
 
The product of the slopes, \(m_1 \times m_2\) \(=\) .
 
The line \(r\) is  to the line \(s\).