Calculating The Shaded Area Circle Inscribed In A Regular Hexagon

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Finding the area of geometric figures, especially when dealing with circles and polygons, often involves a blend of geometric principles and algebraic manipulation. This article delves into an intriguing problem involving a circle inscribed within a regular hexagon, aiming to determine the area of the shaded region – the area within the hexagon but outside the circle. We'll explore the properties of regular hexagons, the relationship between inscribed circles and their circumscribing polygons, and how to leverage 30-60-90 triangles to arrive at the solution. Let's embark on this geometric journey!

Problem Statement Understanding

At the heart of our challenge lies a regular hexagon, a six-sided polygon with all sides of equal length and all interior angles equal. Within this hexagon, a circle is perfectly inscribed, meaning it touches each side of the hexagon at exactly one point. The side length of the hexagon is given as 10 feet. Our mission is to calculate the area of the shaded region – the space enclosed by the hexagon but lying outside the circle. This problem requires us to understand the geometry of both regular hexagons and circles, and how they interact when one is inscribed within the other. The key to unlocking this problem lies in understanding the relationship between the hexagon's dimensions and the circle's radius, and how we can utilize special right triangles to find these dimensions. This involves visualizing the problem, breaking it down into smaller, manageable parts, and applying relevant geometric formulas. A clear understanding of the problem statement is the first step towards a successful solution, allowing us to strategize our approach and identify the necessary tools and techniques. Remember, geometry problems often benefit from a visual representation, so sketching the figure can be immensely helpful in grasping the relationships between the different elements involved. By carefully dissecting the problem statement, we set the stage for a methodical and accurate solution.

Deciphering the Regular Hexagon

A regular hexagon, a cornerstone of this problem, possesses unique geometric characteristics that are crucial to our solution. Let's delve into its properties and how they relate to the inscribed circle. The most important aspect of a regular hexagon is its symmetry. It can be divided into six congruent equilateral triangles by drawing line segments from the center of the hexagon to each vertex. This decomposition is key to understanding the hexagon's geometry and its relationship with the inscribed circle. Each of these equilateral triangles has angles of 60 degrees, and all sides are equal in length. Since the side length of the hexagon is given as 10 feet, each side of these equilateral triangles is also 10 feet. Now, consider the inscribed circle. Its center coincides with the center of the hexagon. The radius of the inscribed circle is the perpendicular distance from the center of the hexagon to the midpoint of any side. This distance is also the altitude of one of the equilateral triangles we discussed earlier. To find this altitude, we can bisect one of the equilateral triangles, creating a 30-60-90 right triangle. This special right triangle is the bridge that connects the hexagon's side length to the circle's radius. Understanding the relationships within this 30-60-90 triangle is paramount to solving the problem. By recognizing and utilizing the properties of the regular hexagon, particularly its decomposition into equilateral triangles and the connection to the inscribed circle via 30-60-90 triangles, we can establish the foundation for calculating the areas needed to find the shaded region. This step-by-step breakdown allows us to approach the problem systematically and efficiently.

The 30-60-90 Triangle Connection

The 30-60-90 triangle is a special right triangle whose angles measure 30 degrees, 60 degrees, and 90 degrees. Its sides have a specific ratio: if the shortest leg (opposite the 30-degree angle) has a length of x, then the longer leg (opposite the 60-degree angle) has a length of x√3, and the hypotenuse (opposite the 90-degree angle) has a length of 2x. This ratio is crucial in solving many geometry problems, including this one. As we discussed earlier, bisecting one of the equilateral triangles that make up the hexagon creates a 30-60-90 triangle. In our case, the hypotenuse of this triangle is half the side length of the equilateral triangle (which is also the side length of the hexagon), so it measures 10 feet / 2 = 5 feet. This is also not the hypotenuse, the hypotenuse will be the side length of the equilateral triangle, which is 10 feet, not 5 feet. The shortest leg is half the side length of the equilateral triangle, which is 5 feet. The longer leg, which is the radius of the inscribed circle, is then 5√3 feet. This is where the 30-60-90 triangle ratio comes into play. By correctly identifying the sides and applying the ratio, we can accurately determine the radius of the circle. This radius is a critical piece of information, as it's needed to calculate the circle's area. Understanding and applying the properties of 30-60-90 triangles is a fundamental skill in geometry. In this problem, it allows us to bridge the gap between the hexagon's side length and the circle's radius, paving the way for the final area calculations. Mastering this concept opens doors to solving a wide array of geometric challenges.

Calculating the Areas: Hexagon and Circle

With the geometric relationships established, we now shift our focus to calculating the areas required to determine the shaded region. This involves finding the area of the regular hexagon and the area of the inscribed circle. The area of a regular hexagon can be calculated in a couple of ways. One method is to use the formula: Area = (3√3 / 2) * s², where s is the side length of the hexagon. In our case, s = 10 feet, so the area of the hexagon is (3√3 / 2) * 10² = 150√3 square feet. Another method is to recall that the hexagon is composed of six equilateral triangles. The area of each equilateral triangle is (√3 / 4) * s², so the area of one triangle is (√3 / 4) * 10² = 25√3 square feet. Multiplying this by 6 (the number of triangles) gives us the same hexagon area: 150√3 square feet. Now, let's calculate the area of the inscribed circle. The formula for the area of a circle is Area = πr², where r is the radius. We determined earlier that the radius of the circle is 5√3 feet. So, the area of the circle is π * (5√3)² = π * 75 = 75π square feet. By systematically applying the area formulas for both the hexagon and the circle, we've obtained the necessary values to find the shaded region. This step highlights the importance of knowing and correctly applying geometric formulas. With these areas in hand, we are now one step closer to solving the problem.

Unveiling the Shaded Region Area

The final step in our geometric journey is to calculate the area of the shaded region. This region, as we defined earlier, is the area within the hexagon but outside the circle. To find it, we simply subtract the area of the circle from the area of the hexagon. We calculated the area of the hexagon to be 150√3 square feet and the area of the circle to be 75π square feet. Therefore, the area of the shaded region is 150√3 - 75π square feet. This result can be left in this exact form, or we can approximate it using a calculator. Using the approximations √3 ≈ 1.732 and π ≈ 3.1416, we get: Area ≈ 150 * 1.732 - 75 * 3.1416 ≈ 259.8 - 235.62 ≈ 24.18 square feet. Thus, the area of the shaded region is approximately 24.18 square feet. By performing this final subtraction, we have successfully solved the problem. This step underscores the elegance of geometric problem-solving – combining individual calculations to arrive at the final answer. The result provides a concrete measure of the shaded area, completing our exploration of this geometric puzzle. This final calculation brings closure to our problem-solving process, showcasing the power of combining geometric principles and algebraic techniques to unravel complex spatial relationships.

Conclusion: A Symphony of Geometry

In conclusion, determining the area of the shaded region within a regular hexagon circumscribing a circle was a multifaceted problem that showcased the beauty and interconnectedness of geometric concepts. We began by carefully understanding the problem statement, recognizing the key elements of a regular hexagon and an inscribed circle. We then delved into the properties of regular hexagons, emphasizing their decomposition into equilateral triangles and the crucial role of the 30-60-90 triangle. This special right triangle served as the bridge between the hexagon's side length and the circle's radius, allowing us to calculate the radius accurately. We then applied the formulas for the areas of both the hexagon and the circle, obtaining the necessary values for the final calculation. Finally, we subtracted the circle's area from the hexagon's area to reveal the area of the shaded region. This problem served as a valuable exercise in applying geometric principles, utilizing special right triangles, and performing area calculations. It also highlighted the importance of systematic problem-solving – breaking down a complex problem into smaller, manageable steps. The solution, approximately 24.18 square feet, represents the culmination of our geometric exploration. This journey through the world of hexagons, circles, and 30-60-90 triangles underscores the power and elegance of geometry in describing and quantifying spatial relationships. By mastering these concepts, we equip ourselves with the tools to tackle a wide range of geometric challenges, appreciating the logical and aesthetic harmony inherent in the world of shapes and sizes.