Need help with a triangle's length side/ angle relation.

Thread starter Dyatlov
Start date May 31, 2015
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Angle Length Relation

In summary, to find the length of a side in a triangle, you can use the Pythagorean theorem or trigonometric ratios. To find the measure of an angle, you can use the law of cosines or law of sines, or trigonometric ratios for a right triangle. The lengths of the sides in a triangle are related by the Pythagorean theorem or the law of cosines/sines. The angle-side-angle congruence criterion can be used to solve for a missing side or angle in a triangle. It is possible to find the length of a side or measure of an angle in a triangle with limited information, but additional information may be needed.

May 31, 2015

Dyatlov

Hello.
I am trying to wrap my head around where from did he got the x = sin of theta equation at the 32:44 mark of the video: .
Isn't sine of theta x over the hypotenuse in the diagram ?
Thanks in advance!

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May 31, 2015

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Dyatlov said:

Isn't sine of theta x over the hypotenuse in the diagram ?

Yes it is, and the length of the hypotenuse (=the pendulum arm) seems to be 1.

Related to Need help with a triangle's length side/ angle relation.

1. How do I find the length of a side in a triangle?

To find the length of a side in a triangle, you can use the Pythagorean theorem, which states that in a right triangle, the square of the length of the hypotenuse (the side opposite the right angle) is equal to the sum of the squares of the other two sides. You can also use trigonometric ratios to find the length of a side in any triangle.

2. How do I find the measure of an angle in a triangle?

To find the measure of an angle in a triangle, you can use the law of cosines or the law of sines, depending on the information you have about the triangle. You can also use trigonometric ratios to find the measure of an angle in a right triangle.

3. What is the relationship between the lengths of the sides in a triangle?

In a right triangle, the lengths of the sides are related by the Pythagorean theorem. In any triangle, the lengths of the sides are related by the law of cosines or the law of sines. Additionally, the sum of the lengths of any two sides of a triangle must be greater than the length of the third side.

4. How do I use the angle-side-angle (ASA) congruence criterion to solve for a missing side or angle in a triangle?

The angle-side-angle (ASA) congruence criterion states that if two triangles have two congruent angles and the included side between the angles is also congruent, then the triangles are congruent. This can be used to solve for a missing side or angle in a triangle by setting up an equation and solving for the unknown variable.

5. Is it possible to find the length of a side or measure of an angle in a triangle if I only know the lengths of two other sides or measures of two other angles?

Yes, it is possible to find the length of a side or measure of an angle in a triangle if you know the lengths of two other sides or measures of two other angles. You can use the law of cosines or the law of sines to solve for the missing side or angle. However, you may need to use additional information, such as the sum of the angles in a triangle being 180 degrees, to solve for the unknown variable.