Isosceles Triangle Side Calculation Perimeter 60cm And Difference 12cm

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In geometry, an isosceles triangle is a triangle that has two sides of equal length. These two sides are called the legs of the triangle, and the third side is called the base. The angles opposite the legs are also equal. Understanding the properties of isosceles triangles is crucial for solving various geometric problems. In this article, we will delve into a specific problem involving an isosceles triangle and explore how to calculate the length of its sides using the given information. The problem we will address is this: The perimeter of an isosceles triangle is 60 cm, and the difference between the length of a leg and the base is 12 cm. Find the length of the leg. This problem requires us to utilize our knowledge of the properties of isosceles triangles and algebraic equations to arrive at the solution. Let's embark on this geometric journey and unravel the solution step by step.

Understanding Isosceles Triangles

Before we dive into the solution, let's recap the fundamental properties of isosceles triangles. An isosceles triangle, by definition, has two sides of equal length. These sides are referred to as the legs, while the third side is called the base. A critical property of isosceles triangles is that the angles opposite the legs are also congruent, meaning they have the same measure. This property is often used in geometric proofs and problem-solving.

Another important characteristic of a triangle, including isosceles triangles, is that the sum of its interior angles is always 180 degrees. This fact is instrumental in finding the missing angles when some angles are known. The perimeter of any triangle is the sum of the lengths of its three sides. In the case of an isosceles triangle, the perimeter is the sum of the lengths of the two legs and the base. Understanding these properties will be instrumental in solving the problem at hand.

Problem Setup

Now, let's set up the problem mathematically. We are given that the perimeter of the isosceles triangle is 60 cm. This means that if we add the lengths of the two legs and the base, we get 60 cm. We are also given that the difference between the length of a leg and the base is 12 cm. Let's denote the length of each leg as 'x' cm and the length of the base as 'y' cm. Based on the given information, we can form two equations:

  1. The perimeter equation: 2x + y = 60 (since there are two legs of length x)
  2. The difference equation: x - y = 12

These two equations form a system of linear equations. Our goal is to solve this system to find the values of 'x' and 'y', which will give us the lengths of the legs and the base of the triangle. We can use various methods to solve this system, such as substitution or elimination. In the next section, we will explore how to solve this system using the substitution method.

Solving the Equations

To solve the system of equations, we will use the substitution method. This method involves solving one equation for one variable and then substituting that expression into the other equation. Let's start with the difference equation: x - y = 12. We can solve this equation for x by adding y to both sides:

x = y + 12

Now we have an expression for x in terms of y. We can substitute this expression into the perimeter equation: 2x + y = 60. Replacing x with (y + 12), we get:

2(y + 12) + y = 60

Now we have an equation with only one variable, y. Let's simplify and solve for y:

2y + 24 + y = 60

3y + 24 = 60

3y = 36

y = 12

So, the length of the base (y) is 12 cm. Now that we have the value of y, we can substitute it back into the equation x = y + 12 to find the value of x:

x = 12 + 12

x = 24

Therefore, the length of each leg (x) is 24 cm. We have successfully solved the system of equations and found the lengths of the sides of the isosceles triangle.

Verifying the Solution

Before we conclude, it's always a good practice to verify our solution to ensure it satisfies the given conditions. We found that the lengths of the legs are 24 cm each, and the length of the base is 12 cm. Let's check if these values satisfy the given conditions:

  1. Perimeter: 2x + y = 2(24) + 12 = 48 + 12 = 60 cm. This matches the given perimeter.
  2. Difference: x - y = 24 - 12 = 12 cm. This matches the given difference between the leg and the base.

Since our solution satisfies both conditions, we can confidently say that our solution is correct. The lengths of the legs of the isosceles triangle are 24 cm each, and the length of the base is 12 cm. Verifying the solution is a crucial step in problem-solving, as it helps to identify any potential errors and ensures the accuracy of the final answer.

Conclusion

In this article, we tackled a geometric problem involving an isosceles triangle. We were given the perimeter of the triangle and the difference between the length of a leg and the base, and our goal was to find the length of the leg. We started by understanding the properties of isosceles triangles and then set up a system of linear equations based on the given information. We used the substitution method to solve the system and found the lengths of the legs and the base. Finally, we verified our solution to ensure its accuracy. This problem demonstrates how algebraic techniques can be applied to solve geometric problems. By understanding the properties of geometric shapes and using algebraic equations, we can solve a wide range of mathematical problems. The key is to break down the problem into smaller, manageable steps and apply the appropriate concepts and techniques. This exercise not only reinforces our understanding of isosceles triangles but also highlights the interconnectedness of different branches of mathematics. Solving geometric problems often involves a combination of geometric principles and algebraic manipulations, making it a valuable skill in mathematical problem-solving.