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Helen [10]
3 years ago
13

Y is inversy proportional to x. When y=7 , x=9 A) work out an equation connecting y and x? B) work out the value of y when x=21

Mathematics
1 answer:
natita [175]3 years ago
8 0

Answer:

see explanation

Step-by-step explanation:

since y is inversely proportional to x the equation relating them is

y = \frac{k}{x} ← k is the constant of proportionality

to find k use the given condition when y = 7, x = 9

k = yx = 7 × 9 = 63

y = \frac{63}{x} ← is the equation connecting them

when x = 21, then

y = \frac{63}{21} = 3


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Answer:

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Step-by-step explanation:

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