Question

What type of slopes do parallel lines have? And, What type of slopes do perpendicular lines have?

Answer 1

The parallel lines have the same slope.

Let

`k:y=m_1x+b_1,\ l:y=m_2x+b_2\\\\l\ ||\ k\iff m_1=m_2`

Perpendicular lines have the negative and reciprocal slopes.

`l\ \perp\ k\iff m_1m_2=-1\to m_2=-(1)/(m_1)`

Answer 2

parallel lines have the same slope

perpendicular lines have the negative reciprocal

ie 3--------> -1/3