The part (a) of this question was well attempted. It involved the expansion of the expression and comparing the coefficients. It did not pose much problems to the candidates. Candidates were able to expand the expression to get 3 - 5 + - 10 which with a little computation gave a = -7 and b = -4. However many candidates expanded but did not compare the coefficients.
In part (b) of the question, the fundamental laws of indices were required to solve this problem. They were to express the right hand side of the equation in powers of 2 and equate the coefficients of both sides to get y= 1. Most candidates did well in this question but there were a significant number who were not able to apply the laws correctly.