BECE Mathematics 2019 Paper

Concept:The gradient of a straight line is the ratio of the change in $y$ to the change in $x$ between two points on the line.Explanation:Let the two given points be $(x_1,y_1) = (-3,4)$ and $(x_2,y_2) = (3,-2)$.The formula for gradient is $m = \frac{y_2 - y_1}{x_2 - x_1}$.Substitute the coordinates: $m = \frac{-2 - 4}{3 - (-3)}$.Simplify the numerator: $-2 - 4 = -6$.Simplify the denominator: $3 - (-3) = 3 + 3 = 6$.Therefore, $m = \frac{-6}{6} = -1$.Answer:The gradient of the straight line is $-1$.Hence, the correct option is D. $-1$.