I will be grateful for anyone's help and give a medal!
Prove that a line that divides two sides of a triangle proportionally is parallel to the third side.

Question

I will be grateful for anyone's help and give a medal!
Prove that a line that divides two sides of a triangle proportionally is parallel to the third side.

flcon04 · Answer

This should help! http://openstudy.com/updates/532a5a7de4b0b2b299b9f1dd

aurorab · Answer

@flcon04 ya know I've seen the same answer like from three different people in other posted questions but I'm still struggling. Thank you though!

dan815 · Answer

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dan815 · Answer

if the sides are proportional, then there are 2 similar triangles, with the same angles as shown above.

if those angles are equal then by some parallel line theorem those lines must be parallel

dan815 · Answer

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