SAT Question 3c5b19ef: Two-variable Data Models And Scatterplots answer and explanation with Desmos solution

Choice A is correct. An equation of a line of best fit can be written in the form $y=a+bx$, where $a$ is the $y$-intercept of the line and $b$ is the slope. In the scatterplot shown, the line of best fit intersects the $y$-axis just over halfway between $10,000$ and $20,000$, or approximately $16,000$. The line of best fit also intersects the graph at the point $(5,40,000)$. Using the slope formula $b=\frac{y_2-y_1}{x_2-x_1}$ and two points that lie on the graph such as $(5,40,000)$ and $(0,16,000)$, the slope can be approximated as $\frac{40,000-16,000}{5-0}$, or $4,800$. Only choice A has a $y$-intercept near the estimate of $16,000$ and a slope near the estimate of $4,800$. Therefore, an equation of the line of best fit could be $n=16,090+4,680t$.