Posted by Shin on Thursday, April 28, 2011 at 2:43pm.
Hooke's Law the table shows the distance D that a spring stretches when a weight W is hung on it.
W (pounds 2 6 9 15
D (inches) 1.6 4.8 7.2 12
(a.) Do the data represent direct or inverse variation?
Explain. (b.) Find an equation that models the data.
(c.) How far will the spring stretc if an 11 pound weight is hung on it, as depicted in the figure?

College Math  MathMate, Thursday, April 28, 2011 at 3:30pm
(a) when the ratios are proportional they represent direct variation.
For example: 1.5/2 = 4.8/6 = 7.2/9 = 12/15 = 0.8
Guess at this point you can figure out the equation required for (b).
(c) substitute W=11 into the equation in (b).
Post for checking if you wish.