Question

If y varies directly as x, and y = 20 when x = 4, find y when x = -6.

Answer 1

y=kx is what is meant by the saying y varies directly as x

Answer 2

Now we can find the constant k since we know that y=20 when x=4

Answer 3

So replacing y with 20 and x with 4
what does that make k?

Answer 4

k will be 5 right?

Answer 5

That is right! You get a present. :)

Answer 6

Now so we know k is a constant which means it never changes so we have
y=5x

Answer 7

But we want to know y when x=-6

Answer 8

is it -30?

Answer 9

Yes omg you are totally and undoubtedly right! :)

Answer 10

Awesome job! :)

Answer 11

thanks so much. i'm learning more from this site than my class. haha. god speed