Show that line 5y=12x−205y = 12x - 205y=12x−20 is perpendicular to line 12y=−5x+8412y = -5x + 8412y=−5x+84, giving the gradients of the two lines in exact form
130 exam-style questions on Eduqas GCSE Maths Perpendicular Lines and the equation of a tangent. Each one has a worked solution and a mark scheme showing where the marks go.