Question

If y varies inversely as x and k = 8, find x when y = 8. 1 8 64

Answer 1

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

Answer 2

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

$y\propto\dfrac{1}{x}\\\\\Rightarrow y=k\times\dfrac{1}{x}\\\\\Rightarrow y=\dfrac{8}{x}~~~~~~~~~~~~~~~~~~(i)$

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

$y=\dfrac{8}{x}\\\\\\\Rightarrow 8=\dfrac{8}{x}\\\\\\\Rightarrow x=\dfrac{8}{8}\\\\\\\Rightarrow x=1.$

Thus, the required value of x is 1.

Option (A) is CORRECT.