Chapter 8 - Coordinate Geometry and Linear Systems - 8.4 - Writing Equations of Lines - Problem Set 8.4 - Page 360: 3

$x-2y=7$

Using $y-y_1=m(x-x_1)$ or the Point-Slope Form, the equation of the line with the given point $( -3,-5 )$ and slope $m= \dfrac{1}{2} $ is \begin{array}{l}\require{cancel} y-(-5)=\dfrac{1}{2}(x-(-3)) \\\\ y+5=\dfrac{1}{2}(x+3) \\\\ 2(y+5)=1(x+3) \\\\ 2y+10=x+3 \\\\ -x+2y=3-10 \\\\ -x+2y=-7 \\\\ x-2y=7 .\end{array}