Can you find the length of ON using Pythagoras and similarity?

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Discussion Overview

The discussion revolves around calculating the length of segment ON using the Pythagorean theorem and the properties of similar triangles. Participants explore the relationship between the dimensions of two right triangles, focusing on the application of similarity and proportionality in their calculations.

Discussion Character

  • Exploratory, Technical explanation, Mathematical reasoning

Main Points Raised

  • One participant expresses confusion about how to use the height of 24 to find the length of ON, suggesting it may relate to properties of right triangles.
  • Another participant asserts that the Pythagorean theorem can be applied to determine the hypotenuse of the smaller triangle, and mentions the similarity of the triangles due to equal angles.
  • A subsequent post reiterates the use of the Pythagorean theorem for the smaller triangle and proposes a method to find the larger triangle's dimensions by applying proportionality, although the participant is uncertain about calculating the height or hypotenuse.
  • A later reply introduces a formula for segment NO based on similarity, calculating it as 30, and then applies the Pythagorean theorem to find the length of OP, resulting in an expression involving the square root of 34.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the method for calculating the height or hypotenuse of the larger triangle, and there are varying levels of understanding regarding the application of similarity and the Pythagorean theorem.

Contextual Notes

Some assumptions about the triangles' dimensions and relationships remain unverified, and the discussion includes unresolved steps in the calculations presented.

alextrainer
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In attached file, I understand 50 is the base; no idea how to use the 24 height to calculate length of ON - must have to do with property of right triangles?

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These are, of course, right triangles so you can use the Pythagorean theorem To determine the length of the hypotenuse of the small triangle. Then, since the angles of the large and small triangles are the same, they are similar triangles. Corresponding parts of the two right triangles are proportional.
 
HallsofIvy said:
These are, of course, right triangles so you can use the Pythagorean theorem To determine the length of the hypotenuse of the small triangle. Then, since the angles of the large and small triangles are the same, they are similar triangles. Corresponding parts of the two right triangles are proportional.

Thanks for the smaller triangle I get hypotenuse of 46.65. Then each leg and hypotenuse is multipled by a proportion?

So larger triangle would be 50 leg - no idea how to figure height or hypotenuse unless I multiple by 10/40 percent all the known lengths.
 
Let:

$$\overline{NO}=x$$

Then, by similarity, we may state:

$$\frac{x}{50}=\frac{24}{40}=\frac{3}{5}$$

Hence:

$$x=50\cdot\frac{3}{5}=10\cdot3=30$$

And then by Pythagoras:

$$\overline{OP}=\sqrt{30^2+50^2}=10\sqrt{3^2+5^2}=10\sqrt{34}$$
 

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