Let's calculate the straight line equation
To do this we will take two points from the graph
A = (0,3)
B= (2,0)
For them we will first calculate the slope of the curve
[tex]m=\frac{y2-y1}{x2-x1}[/tex][tex]\begin{gathered} m=\frac{0-3}{2-0} \\ m=\frac{-3}{2} \end{gathered}[/tex]Now let's calculate the y-axis intersection
[tex]\begin{gathered} b=y-mx \\ b=3-m\cdot0 \\ b=3 \end{gathered}[/tex]The equation of the line in the slope-intercept form is
[tex]y=-\frac{3}{2}x+3[/tex]