Question

Draw the graph of y = 2x² – 3x – 5 and hence solve 2x² – 4x – 6 = 0. y = 2x² – 3x – 5

Answer 1

Draw the parabola using the points (-4, 39), (-3, 22), (-2, 9), (-1, 0), (0, -5), (1, -6), (2, -3), (3, 4), (4, 15).

To solve 2x² – 4x – 6 = 0, subtract it from y = 2x² – 3x – 5

Draw a straight line using the points (-2, -1), (0, 1), (2, 3). The points of intersection of the parabola and the straight line forms the roots of the equation. The x-coordinates of the points of intersection forms the solution set. 

∴ Solution {-1, 3}