# "Recall the definition of the slope of a line between two points: " #
# \quad "slope of line between" \ ( x_1, y_1 ) \quad "and" \quad ( x_2, y_2 ) \ = \ { y_2 - y_1} / { x_2 - x_1}. #
# "Applying this definition to our two given points, we get:" #
# \quad "slope of line between" \ ( 1, 2 ) \quad "and" \quad ( 2, 5 ) \ = \ { (5) - (2) } / { (2) - (1) } #
# \qquad \qquad \qquad \qquad \qquad \qquad \qquad \qquad \qquad \qquad \qquad \qquad \qquad \qquad \qquad \qquad \qquad = \ { 3 } / { 1 } \ = \ 3. #
# "So, we conclude:" #
# \qquad \qquad "slope of line between" \ ( 1, 2 ) \quad "and" \quad ( 2, 5 ) \ = \ 3 \ . #