SAT Mathematics Practice Test 5

From the graph, the y-intercept of line $\mathit{l}$ is (0, 1). The line also passes through the point $\left(1,2\right)$. Therefore the slope of the line is $\frac{2-1}{1-0}=\frac{1}{1}=1$,and in slope-intercept form, the equation for line $\mathit{l}$ is $\mathit{y}=\mathit{x}+1$
Choice A is incorrect. It is the equation of the vertical line that passes through the point $\left(1,0\right)$.Choice B is incorrect. It is the equation of the horizontal line that passes through the point $\left(0,1\right).$ Choice C is incorrect. The line defined by this equation has y-intercept $\left(0,0\right)$, whereas line has y-intercept $\left(0,1\right).$