When asked to solve a quadratic equation, we are really finding the roots – where the parabola cuts the x-axis, therefore when we have the graph drawn, it is very easy to do this. Looking at the graph ...

For example, the simultaneous equations \(3a + 2b = 17\) and \(4a - b = 30\) have no common coefficient as the coefficients of \(a\) are 3 and 4, and the coefficients of \(b\) are 2 and -1. Remember ...