If the slope of a line passing through the points A(2, 1) and B(3, y) is 4, then the value of y will be:

5

The correct answer is Option (3) → 5

The slope of a line passing through $(x_1, y_1)$ and $(x_2, y_2)$ is:

$m = \frac{y_2 - y_1}{x_2 - x_1}$

Here:
$(x_1, y_1) = (2, 1),(x_2, y_2) = (3, y),m = 4$

$4 = \frac{y - 1}{3 - 2} = y – 1$

$y−1=4  ⟹  y=5$