Question #N992

In the $xy$-plane, line $k$ passes through the points $(2,-1)$ and $(4,3)$. What is the slope of line $k$?
A. -2
B. -1
C. 2
D. 4

Correct Answer is: C

The slope of a line passing through two points $(x_1, y_1)$ and $(x_2, y_2)$ can be calculated using the formula: $m = \frac{y_2 - y_1}{x_2 - x_1}$. Substituting the points (2, -1) and (4, 3) into the formula, we get: $m = \frac{3 - (-1)}{4 - 2} = \frac{4}{2} = 2$. Therefore, the slope of line $k$ is 2.