SOLUTION: the value of y varies with x and y=12 when x=-6 find y when x=-4

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Question 567928: the value of y varies with x and y=12 when x=-6 find y when x=-4
Answer by Horlaye(27) About Me  (Show Source):
You can put this solution on YOUR website!
Y varies as x
y=kx ( where k is the constant )
then we subtitute for the values of y and x to know the value of our constant.
12=-6k, divide both sides by the co-efficient of k
therefore k=-2
(y=-2x) :the law of variation.
Hence find y when x=-4
y=-2x
y=-2(-4)
y=8