Posted by JaneLee on Monday, January 28, 2008 at 12:59pm.
1. If y varies directly as x, and y=30 when x=4, find the constant of proportionality.
2. If y varies inversely as x, and y=2 when x=10, find x when y=4.
3. If a varies jointly as b and c, and a=10, when b=12 and c=2, find a when b=8 and c=1/2.

Algebra II  jAKE1214, Monday, January 28, 2008 at 1:25pm
1. y=kx plug in your # and solve for k
2. y=k/x solve for k and then plug in your y=4 to find x with the k value you found.
3. I forgot how to do this one.. it's been years lol. 
Algebra IIB  Anonymous, Wednesday, October 12, 2016 at 11:55am
50