If y varies inversely as x and y = 3 when x = 14, find x when y = 6.

Question

The answer options are:

a) x=7

b) x=42

c) x=6

d) x=3

Answer 1

X=7 What you can do is look at the first two values given, and make them x1 and y1. Then your next value here is y2.

So x1 is 14, and y1 is 3. y2 becomes 6. X2 is unknown.

Then make the formula: x1/y2 is equal to x2/y1

(You are setting two fractions equal to each other)

That makes 14/6=X/3. When we cross multiply, we find that x=7.

Answer 2

Hi Abby,

when two numbers are inversely proportional , we multiply them to get the constant which is a product. Soon this case x= 14 and y = 3 . The product or constant is 42.

so if y= 6 , 42/y = x

substituting 42/6= x

x= 7

answer a.

i hope this helps