Exercise 66 Page 290

To write the equation of a line perpendicular to the given equation, we first need to determine its slope. After that, we will write a general equation and use the given point to determine the $y\text{-}$intercept.

Calculating the Perpendicular Line's Slope

Two lines are perpendicular when their slopes are negative reciprocals. This means that the product of a given slope and the slope of a line perpendicular to it will be $\text{-}1.$ For any equation written in slope-intercept form, $y=mx+b,$ we can identify its slope as the value of $m.$ Looking at the given equation, we can see that its slope is $\text{-}3.$