The answer is J.
The reason why is because of the proportions to each intersection of linesare equal to each other (each is SIMILAR, like forming a triangle). In this case, they will both end up having the same fraction but in different form.
So, for the smaller set on the right the fraction is 8.5/5, meaning the fraction is width/height.
The same will go for the left one: width/height. This means that the left will be 29/h.
So, the answer is J. 29/h=8.5/5.