Question

Help ASAP
For the inverse variation equation xy = k, what is the constant of variation, k, when x = –3 and y = –2

Answer 1

–6
-2/3
3/2
6

Answer 2

Any ideas?

Answer 3

-2/3 would be my guess

Answer 4

Guessing randomly doesn't work in math :-)

Please give a reason.

Answer 5

because usually its x/y right? so the inverse would be y/x

Answer 6

You are correct that "usually" you see expressions like x/y in class

and the inverse of x/y is y/x,

but that is not what this question is asking for.

Answer 7

So its 6?

Answer 8

no that doesnt make sense

Answer 9

Yes. 6 is correct :-)

Answer 10

For the inverse variation equation xy = k,

what is the constant of variation, k,

when x = –3 and y = –2

x * y = k
-3 (-2) = 6

Answer 11

Thank you! Can you help me with another one?

Answer 12

I can try.

Answer 13

The inverse variation equation shows the relationship between wavelength in meters, x, and frequency, y.
y=3x10^8/x
What is the wavelength for radio waves with frequency 3 × 10^9?

1 × 10^–1 m
3 × 10^–1 m
3 × 10^17 m
9 × 10^17 m

Answer 14

Any ideas?

Answer 15

so find y=3x10^8/x

Answer 16

Read the problem carefully.

Decide what unknown number is being asked for.

Answer 17

3x10^9?

Answer 18

that's not an answer choice

Answer 19

I still dont understand

Answer 20

what is the question asking for?

Answer 21

What is the wavelength for radio waves with frequency 3 × 10^9

Answer 22

Good, where is the wavelength in the formula they gave you?

Answer 23

wavelength is x and frequency is y

Answer 24

so they want you to find x, right?

Answer 25

yes