Question

If y varies inversely as x and k = 8, find x when y = 8.

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Answer 1

Answer: The correct option is (A). 1.

Step-by-step explanation: Given that y varies inversely as x and k = 8.

We are to find the value of x when y = 8.

Since y varies inversely as x, so we have

`y\propto(1)/(x)\\\\\Rightarrow y=k*(1)/(x)\\\\\Rightarrow y=(8)/(x)~~~~~~~~~~~~~~~~~~(i)`

When y = 8, we get from equation (i) that

`y=(8)/(x)\\\\\\\Rightarrow 8=(8)/(x)\\\\\\\Rightarrow x=(8)/(8)\\\\\\\Rightarrow x=1.`

Thus, the required value of x is 1.

Option (A) is CORRECT.

Answer 2

The answer is 1

y varies inversely as x:
y = k/x

We have:
k = 8
y = 8
x = ?

y = k/x
x = k/y
x = 8/8
x = 1