collapsable rhombus: maximum length of shaft

[kkhewett]

Ta word problem shows a picture of a car jack constructed like a rhombus- partially extended. The question is-- if the sides of this rhombus are 13 inches, what is the maximum length of the shaft??
(The shaft is the big screw running through the middle of the jack)

Am I on the right track to be adding the length of two sides to get a total of 26 inches. Is this the maximum length of the shaft.
I am thinking of if it is totally close down, ithe shaft would have to be long enough to hold the length of both sides of the rhombus put together. It would almost form a steraight line when closed down.
Is 26 the correct answe??? I need some input here please. And please be gentle with me ...geometry is not my fav subject!!
KK

[maggiemagnet]

I think you've got the right answer, but it can be hard to tell when the problem is "real world". I mean, if you did the jack all the way until it's nearly "collapsed" (straight), you'd still need a little extra on the shaft so the threaded part doesn't fall out of the holes. But I would probably give the same answer that you have.