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2 years ago

Y varies inversely with x if y = 7 when x =-4, find y when x = 5

Mathematics

1 answer:

marysya [2.9K]2 years ago

3 0

Answer:

y = - $\frac{28}{5}$

Step-by-step explanation:

Given y varies inversely with x then the equation relating them is

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

To find k use the condition y = 7 when x = - 4, then

7 = $\frac{k}{-4}$ ( multiply both sides by - 4 )

- 28 = k

y = $\frac{-28}{x}$ ← equation of variation

When x = 5 , then

y = $\frac{-28}{5}$ = - $\frac{28}{5}$

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Y varies inversely with x if y = 7 when x =-4, find y when x = 5​

Y varies inversely with x if y = 7 when x =-4, find y when x = 5