The table at the right shows that y varies inversely as x. What is the value of y when x is 12?

Question

What does inversely mean?

Here's (kind of) what the table looked like:

x: 4; 6; 16; 36
y: 72;48; 18; 8

Thank you!

Answer 1

inversely ----> did you notice that as x increases, the value of y decreases ?

y varies inversely as x
or
y = k(1/x) = k/x
sub in the first number pair
72 = k/4
so k = 288

then your equation is y = 288/x

(check to make sure the other values work, they do)

so if x = 12, y = 288/12 = 24

BTW, if the question had said
y varies 'directly' with x, my equation would have been
y = kx