Line A passes through the points (12,4)\displaystyle \left(\frac{1}{2}, 4\right)(21,4) and (72,6)\displaystyle \left(\frac{7}{2}, 6\right)(27,6). Line B passes through the points (−2,72)\displaystyle \left(-2, \frac{7}{2}\right)(−2,27) and (2,−52)\displaystyle \left(2, -\frac{5}{2}\right)(2,−25). Show that Line A and Line B are perpendicular. Use exact values of the gradients in your working.
204 exam-style questions on WJEC GCSE Maths Parallel and Perpendicular Lines. Each one has a worked solution and a mark scheme showing where the marks go.