WAEC Mathematics 2025 Paper

Concept:Use two points on the straight-line graph to find its slope and equation, then determine the inequality sign from the solid boundary and shaded region.Explanation:From the sketch graph, the line passes through $(0,3)$ and $(1,0)$.The slope $m$ is calculated as:$m = \frac{y_2 - y_1}{x_2 - x_1} = \frac{0 - 3}{1 - 0} = -3$.The equation of a straight line is $y = mx + c$, where $c$ is the $y$-intercept.Here, $c = 3$, so the line equation is $y = -3x + 3$.Since the boundary line is solid, the inequality sign must be either $\leq$ or $\geq$.The shaded region of the graph lies below the line, which gives $y \leq -3x + 3$.Therefore, the inequality illustrated by the graph is $y \leq -3x + 3$.Answer:A. $y \leq -3x + 3$