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Maths

DEFG is a rhombus
G has co-ordinates (9,1)
The equation of diagonal DF is y=0.5x-1
Find an equation for the diagonal DF
Give your answer in the form y=ax+b

anyone any good at this ???
I tried to attach the image as-well x
https://vle.mathswatch.co.uk/images/questions/question16417.png

Reply 1

ashleydixon

For a clue, remember the general equation for a line, given the gradient and two points ( y-y_n=m(x-x_n) ) and recall that the gradient of a perpendicular is the negative reciprocal.

Reply 2

casperyc

You have the GRADIENT of DF, hence the GRADIENT of EG.
You also have a POINT on the line EG.

So given a POINT and the GRADIENT, you can find the equation of the line, using any formula of your choice.