Please help? Prove that a line parallel to one side of a triangle divides the other two sides proportionally.

Question

anonymous · Answer

I tried making a figure but it didn't work out. I don't know what to do.

anonymous · Answer

Is there some theorem that makes this makes sense? I think the question wants a whole proof.

anonymous · Answer

the two triangles will be similar by AAA, and therefor, their sides are proportional

anonymous · Answer

How did you get that?

anonymous · Answer

can not show here because can't draw it here

anonymous · Answer

oh ok

anonymous · Answer

Can you explain it further or anything?

anonymous · Answer

It would be according to my drawing, but without it, it would not make any sense

anonymous · Answer

ok

anonymous · Answer

Anyone else?

anonymous · Answer

@undeadknight26 ? @phi ?

phi · Answer

Prove that a line parallel to one side of a triangle divides the other two sides proportionally.
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