4 years ago

Suppose that y varies directly as x and y = -9 when x = 3. find the value of x when y = 18.

Mathematics

1 answer:

Doss [256]4 years ago

8 0

Direct proportionality
y/x=k
-9/3=k
k=-3
so when y=18
18/x=3
cross multiply
3x=18
divide both sides by 3
3x=18
x=6

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<u>EXPLANATION</u>

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