Chapter 4 - Writing Linear Functions - 4.1 - Writing Equations in Slope-Intercept Form - Monitoring Progress - Page 177: 3

$y=\frac{1}{2}x+1$

Let $(x_{1},y_{1})=(0,1)$ and $(x_{2},y_{2})=(4,3)$ Slope $m=\frac{y_{2}-y_{1}}{x_{2}-x_{1}}=\frac{3-1}{4-0}=\frac{2}{4}=\frac{1}{2}$ Because the line crosses the y-axis at $(0,1)$, the y-intercept $b$ is $1$. Slope-intercept form is $y=mx+b$. Substituting, we get the equation as $y=\frac{1}{2}x+1$