how can an irrational number represent an exact length

Question

freckles · Answer

So basically you are asking how can the circumference of a circle with radius one with be 2pi?

anonymous · Answer

all exact lengths are irrational
rationals are only an approximation

anonymous · Answer

not really @freckles

freckles · Answer

but you do though pi is irrational right?

freckles · Answer

know*

anonymous · Answer

could you perhaps add more detail @@satellite73

anonymous · Answer

i do know @freckles

anonymous · Answer

*@satellite73

anonymous · Answer

@satellite73

freckles · Answer

I don't know if I understand. If you know a circle with radius 1 can have circumference 2pi and you know that pi is irrational, then why are you questioning if irrationals can represent exact lengths?

anonymous · Answer

my math teacher would like us to use triangles @freckles

freckles · Answer

oh ok 
well let's thing about a square for a sec

anonymous · Answer

ok @freckles

freckles · Answer

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say with a side length 1
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and by Pythagorean thm we have
$$1^2+1^2=hyp^2 \ 1+1=hyp^2 \ 2=hyp^2 \ \sqrt{2}=hyp$$
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this triangle has a side length of sqrt(2)