(a) Solve the inequality: \(\frac{1 + 4x}{2}\) -\(\frac{5 + 2x}{7}\) < x -2
(b) If x: y = 3: 5, find the value of \(\frac{2x^2 – y^2}{y^2 – x^2}\)
Explanation
(a) majority of the candidates multiplied through by the L.C.M which is 14 to arrive at 7(1+4x) - 2(5+2x) < 14(x - 2) and when simplified yielded 10x < -25 x -2\(\frac{1}{2}\)
(b) it was expected that they express x = \(\frac{3y}{5}\) or y = \(\frac{5x}{3}\) and thereafter, substitute into the given expression to have \(\frac{2x^2 - y^2}{y^2 - x^2} = \frac{2x^2 - (\frac{5x}{3})^2}{(\frac{5x}{3})^2 - x^2} = \frac{x^(2 - \frac{25}{9})}{x^2(\frac{25}{9} - 1)} = \frac{-7}{16}\)