Relationship Between the Sides

Oct 13, 2025 by wbrum.org 141 views

A 45-45-90 triangle is a special right-angled triangle with two equal angles, each measuring 45 degrees. This unique configuration results in specific relationships between the lengths of the sides. In this article, we will explore the properties of a 45-45-90 triangle and determine which of the given statements is true.

The Structure of a 45-45-90 Triangle

A 45-45-90 triangle consists of two equal legs and a hypotenuse. The legs are the sides that meet at a right angle, while the hypotenuse is the side opposite the right angle. In a 45-45-90 triangle, the two legs are equal in length, and the hypotenuse is longer than each leg.

Relationship Between the Sides

The relationship between the sides of a 45-45-90 triangle can be expressed using the Pythagorean theorem. The theorem states that in a right-angled triangle, the square of the length of the hypotenuse (c) is equal to the sum of the squares of the lengths of the other two sides (a and b). Mathematically, this can be expressed as:

c² = a² + b²

In a 45-45-90 triangle, since the two legs are equal in length, we can substitute a = b into the equation:

c² = a² + a² c² = 2a²

To find the relationship between the length of the hypotenuse and the length of each leg, we can take the square root of both sides of the equation:

c = √2a

This shows that the length of the hypotenuse is √2 times the length of each leg.

Evaluating the Statements

Now that we have established the relationship between the sides of a 45-45-90 triangle, let's evaluate the given statements:

A. Each leg is $\sqrt{3}$ times as long as the hypotenuse.

This statement is false. As we have shown, the length of the hypotenuse is √2 times the length of each leg, not √3.

B. Each leg is $\sqrt{2}$ times as long as the hypotenuse.

This statement is also false. We have shown that the length of the hypotenuse is √2 times the length of each leg, not the other way around.

C. The hypotenuse is $\sqrt{2}$ times as long as either leg.

This statement is true. As we have shown, the length of the hypotenuse is √2 times the length of each leg.

Conclusion

In conclusion, the correct statement about a 45-45-90 triangle is that the hypotenuse is √2 times as long as either leg. This unique relationship is a result of the special configuration of the triangle, with two equal angles and two equal legs. Understanding the properties of a 45-45-90 triangle is essential in mathematics, particularly in geometry and trigonometry.

Applications of 45-45-90 Triangles

45-45-90 triangles have numerous applications in mathematics and real-world problems. Some examples include:

Geometry: 45-45-90 triangles are used to construct geometric shapes, such as squares and rectangles.
Trigonometry: 45-45-90 triangles are used to solve trigonometric problems, such as finding the length of sides and angles.
Engineering: 45-45-90 triangles are used in engineering to design and build structures, such as bridges and buildings.
Computer Science: 45-45-90 triangles are used in computer science to solve problems related to geometry and trigonometry.

Real-World Examples

45-45-90 triangles can be found in various real-world situations, such as:

Building design: 45-45-90 triangles are used in building design to create symmetrical and aesthetically pleasing structures.
Bridge construction: 45-45-90 triangles are used in bridge construction to ensure stability and strength.
Computer graphics: 45-45-90 triangles are used in computer graphics to create 3D models and animations.

Conclusion

A 45-45-90 triangle is a special right-angled triangle with two equal angles, each measuring 45 degrees. This unique configuration results in specific relationships between the lengths of the sides. In this article, we will answer some frequently asked questions about 45-45-90 triangles.

Q: What is a 45-45-90 triangle?

A 45-45-90 triangle is a right-angled triangle with two equal angles, each measuring 45 degrees. This unique configuration results in specific relationships between the lengths of the sides.

Q: What are the properties of a 45-45-90 triangle?

A 45-45-90 triangle has two equal legs and a hypotenuse. The legs are the sides that meet at a right angle, while the hypotenuse is the side opposite the right angle. In a 45-45-90 triangle, the two legs are equal in length, and the hypotenuse is longer than each leg.

Q: What is the relationship between the sides of a 45-45-90 triangle?

c² = a² + b²

In a 45-45-90 triangle, since the two legs are equal in length, we can substitute a = b into the equation:

c² = a² + a² c² = 2a²

To find the relationship between the length of the hypotenuse and the length of each leg, we can take the square root of both sides of the equation:

c = √2a

This shows that the length of the hypotenuse is √2 times the length of each leg.

Q: What is the length of the hypotenuse in a 45-45-90 triangle?

The length of the hypotenuse in a 45-45-90 triangle is √2 times the length of each leg.

Q: Can a 45-45-90 triangle be isosceles?

Yes, a 45-45-90 triangle can be isosceles. Since the two legs are equal in length, the triangle is isosceles.

Q: Can a 45-45-90 triangle be equilateral?

No, a 45-45-90 triangle cannot be equilateral. Since the two legs are equal in length, but the hypotenuse is longer than each leg, the triangle is not equilateral.

Q: What are some real-world applications of 45-45-90 triangles?

45-45-90 triangles have numerous applications in mathematics and real-world problems. Some examples include:

Geometry: 45-45-90 triangles are used to construct geometric shapes, such as squares and rectangles.
Trigonometry: 45-45-90 triangles are used to solve trigonometric problems, such as finding the length of sides and angles.
Engineering: 45-45-90 triangles are used in engineering to design and build structures, such as bridges and buildings.
Computer Science: 45-45-90 triangles are used in computer science to solve problems related to geometry and trigonometry.

Q: Can I use a 45-45-90 triangle to solve a problem in a different context?

Yes, you can use a 45-45-90 triangle to solve a problem in a different context. Since the properties of a 45-45-90 triangle are universal, you can apply them to any problem that involves a right-angled triangle.

Q: How can I use a 45-45-90 triangle to solve a problem in a different context?

To use a 45-45-90 triangle to solve a problem in a different context, you can follow these steps:

Identify the problem and determine if it involves a right-angled triangle.
Draw a diagram of the problem and identify the sides of the triangle.
Use the properties of a 45-45-90 triangle to find the length of the sides.
Apply the properties of a 45-45-90 triangle to solve the problem.

Conclusion

In conclusion, 45-45-90 triangles are a fundamental concept in mathematics, with unique properties and relationships between the sides. Understanding the properties of a 45-45-90 triangle is essential in mathematics, particularly in geometry and trigonometry. By answering some frequently asked questions about 45-45-90 triangles, we have demonstrated the importance of this concept in mathematics and real-world problems.