Julia has to measure an object. she does not have a ruler. tell what julia could do to solve her problem.

Pretty much and in short, make up your own measure.

so... say you can use a tie or something with length, and use that to measure whatever object you need it for.

for example, I can just grab a string, cut it, and measure something, and the measurement may just be that the object is my string 6 times, so I know the length of the object is 6 times the length of the string I cut.

it doesn't quite matter how long the string cut was, all that matters is that is relable or referenciable for reuse.  Later on I could always just get the string measure and convert it to metric, once I found a ruler  or imperial units.

but in the short run, it doesn't really matter the length of the string cut, all that matters is that is referenciable, the object will be 6 times my string cut, here, in France, in Pluto, in Andromeda, anywhere.

bear in mind that the measure units we use today, are only usable because they're referenciable, so if I tell you 15 inches of something, you know how much 15 inches is, so that's all that matters.

That they are numbers and related to each other.

First subtract 10 from both side
y^2+6y-16=0
(y+8)(y-2)=0
-8 and 2