Chapter 2 Linear Equations and Functions - 2.4 Write Equations of Lines - 2.4 Exercises - Skill Practice - Page 102: 29

$y=-0.25x+4.75.$

We know that by the Slope Formula: if $P_1(x_1,y_1)$ and $P_2(x_2,y_2)$ are on a line, then the slope is: $m=\frac{y_2-y_1}{x_2-x_1}$. Hence here: $m=\frac{5-4}{-1-3}=\frac{1}{-4}=-0.25.$ We know that if the slope of a line is $m$ and it contains $P_1(x_1,y_1)$, then its equation is: $y-y_1=m(x-x_1).$ Hence here: $y-4=-0.25(x-3)\\y-4=-0.25x+0.75\\y=-0.25x+4.75.$