SAT Question 03a16790: Two-variable Data Models And Scatterplots answer and explanation with Desmos solution

Choice B is correct. A line of best fit is shown in the scatterplot such that as the value of $x$ increases, the value of $y$ decreases. Thus, the slope of the line of best fit shown is negative. The slope of a line passing through two points, $\left(x_1,y_1\right)$ and $\left(x_2,y_2\right)$, can be calculated as $\frac{y_2-y_1}{x_2-x_1}$. The line of best fit shown passes approximately through the points $\left(1,12\right)$ and $\left(11,4\right)$. Substituting $\left(1,12\right)$ and $\left(11,4\right)$ for $\left(x_1,y_1\right)$ and $\left(x_2,y_2\right)$, respectively, in $\frac{y_2-y_1}{x_2-x_1}$ gives $\frac{4-12}{11-1}$, which is equivalent to $-\frac{8}{10}$, or $-0.8$. Therefore, of the given choices, $-0.8$ is closest to the slope of the line of best fit shown.