SAT Question b2845d88: Linear Equations In Two Variables answer and explanation with Desmos solution

Choice A is correct. The slope of the line can be found by choosing any two points on the line, such as $(4,-2)$ and $(0,-1)$. Subtracting the $y$-values results in $-2-(-1)=-1$, the change in $y$. Subtracting the $x$-values results in $4-0=4$, the change in $x$. Dividing the change in $y$ by the change in $x$ yields $-1÷4=-\frac{1}{4}$, the slope. The line intersects the $y$-axis at $(0,-1)$, so $-1$ is the $y$-coordinate of the $y$-intercept. This information can be expressed in slope-intercept form as the equation $y=-\frac{1}{4}x-1$.