Why is the inverse of a gradient -1/x?
Because the value, x and its inverse, -1/x should multiply together to give -1. This is proof that two lines are perpendicular (or having the same magnitude of gradient but opposite signs +/- ).
SR
Related Maths A Level answers
All answers ▸Find the equation of the line through the following points: (-2, -3) and (1, 5)
Which A-level modules did you take?
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