Chapter 1.4, Problem 7AYU

To determine

Two nonvertical lines have slopes $m_1$ and $m_2$, respectively. The lines are parallel if _______ and the _______ are unequal; the lines are perpendicular if _______.

Answer to Problem 7AYU

Solution:

$m_1=m_2$; $y\text{-intercepts}$; $m_1{m}_2=-1$

Explanation of Solution

Two nonvertical lines have slopes $m_1$ and $m_2$, respectively. The lines are parallel if $m_1=m_2$ and the $y\text{-intercepts}$ are unequal; the lines are perpendicular if $m_1{m}_2=-1$.