Question

find the unknown length y in the following figure​

Answer 1

Answer:

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Similar triangles by rigorous definition means that the angles are the same and the corresponding sides are proportional to each other

In this one you can see the to side is 13 in the original and 6.5 in the copy, its exactly 2:1

And the same for the left side, 17 in the original and 8.5 in thw copy, also 2:1

So the third side of a pair of similar triangles will also have the same proportionality, if the original is 21 as shown, the same side in the copy will be exactly half of that...

Answer 2

Answer:

O y m 5 n 13

length

figure

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