Can someone please help? This is due soon and I have no clue how to do it. Can someone please explain how to do this?

9514 1404 393

  y = 27

Step-by-step explanation:

The altitude of a right triangle creates two triangles that are each similar to each other and to the larger right triangle. This means corresponding sides are proportional.

If we write the proportion for the legs, we get ...

  (long leg) / (short leg) = y/18 = 18/12

Multiplying by 18 gives us ...

  y = 18(18/12)

  y = 27

Additional comment

The leg/leg proportion above gave rise to the relation ...

  altitude² = (left hypotenuse segment)×(right hypotenuse segment)

That is, the altitude is the geometric mean of the two hypotenuse segments it touches. 18 = √(12y)

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There are two other "geometric mean" relationships in this triangle.

Each of these relationships is ultimately derived from the fact that all of the triangles are similar. You really only need to remember that these triangles are all similar and corresponding sides of similar triangles are proportional. (In some cases, it can be a bit of a shortcut if you remember the geometric mean relations.)

the fist one is not equalvalent but i think th second one isand the third isnt definetly or the last one is i think. hope this !

step-by-step explanation:

step-by-step explanation: