Chapter 7: Problem 36
Find the area (in square units) of each triangle described. $$ a=\frac{25}{6}, b=\frac{17}{6}, c=\frac{11}{6} $$
Short Answer
Expert verified
The area of the triangle is approximately 2.118 square units.
Step by step solution
01
Identify the Formula
To find the area of a triangle given its three sides, we use Heron's formula. Heron's formula states that for a triangle with sides of length \(a\), \(b\), and \(c\), the area \(A\) is given by: \[ A = \sqrt{s(s-a)(s-b)(s-c)} \] where \(s\) (the semi-perimeter) is calculated as \(s = \frac{a+b+c}{2}\).
02
Calculate Semi-Perimeter
Using the side lengths \(a = \frac{25}{6}\), \(b = \frac{17}{6}\), and \(c = \frac{11}{6}\), calculate \(s\) as follows: \[ s = \frac{\frac{25}{6} + \frac{17}{6} + \frac{11}{6}}{2} = \frac{\frac{53}{6}}{2} = \frac{53}{12} \]
03
Calculate Each Term of the Formula
Using the calculated semi-perimeter \(s = \frac{53}{12}\), calculate the individual components:- \(s-a = \frac{53}{12} - \frac{25}{6} = \frac{53}{12} - \frac{50}{12} = \frac{3}{12} = \frac{1}{4} \)- \(s-b = \frac{53}{12} - \frac{17}{6} = \frac{53}{12} - \frac{34}{12} = \frac{19}{12} \) - \(s-c = \frac{53}{12} - \frac{11}{6} = \frac{53}{12} - \frac{22}{12} = \frac{31}{12} \)
04
Plug into Heron's Formula
Substitute the values into Heron's formula to find the area:\[ A = \sqrt{\frac{53}{12} \times \frac{1}{4} \times \frac{19}{12} \times \frac{31}{12}} \] Simplify step-by-step to calculate the product:1. \( \frac{53 \times 1 \times 19 \times 31}{12 \times 4 \times 12 \times 12} = \frac{31103}{6912} \)2. \( A = \sqrt{\frac{31103}{6912}} \) The exact value is complicated, so you can find a numerical approximation of this square root.
05
Simplify and Approximate
Let's find the approximate value for better understanding: \[ A \approx \sqrt{\frac{31103}{6912}} \approx 2.118 \] Therefore, the approximate area of the triangle is around 2.118 square units.
Unlock Step-by-Step Solutions & Ace Your Exams!
-
Full Textbook Solutions
Get detailed explanations and key concepts
-
Unlimited Al creation
Al flashcards, explanations, exams and more...
-
Ads-free access
To over 500 millions flashcards
-
Money-back guarantee
We refund you if you fail your exam.
Over 30 million students worldwide already upgrade their learning with 91Ó°ÊÓ!
Key Concepts
These are the key concepts you need to understand to accurately answer the question.
Triangle Area Calculation
Calculating the area of a triangle can be easy if you know the lengths of its sides. One efficient way to determine a triangle's area is using Heron's formula. This formula is especially beneficial when you have a triangle with sides but no height given.
Heron's formula as given by:
Heron's formula as given by:
- First, find the semi-perimeter, denoted as \( s \), of the triangle, which is half of the perimeter.
- Once you've got \( s \), Heron's formula is \( A = \sqrt{s(s-a)(s-b)(s-c)} \).
Semi-Perimeter Calculation
The semi-perimeter of a triangle is a stepping stone to finding its area using Heron's formula. The term "semi" refers to the fact that it involves taking half of the triangle's perimeter. Here's how to find it:
Calculating the semi-perimeter is a critical step, as it leads directly into the application of Heron's formula, setting the stage for calculating the triangle's area.
- First, add the lengths of the sides: \( a + b + c \).
- Then, divide by 2: \( s = \frac{a+b+c}{2} \).
Calculating the semi-perimeter is a critical step, as it leads directly into the application of Heron's formula, setting the stage for calculating the triangle's area.
Square Root Approximation
Once the semi-perimeter \( s \) is known, and all calculations of \( (s-a)(s-b)(s-c) \) are complete, plugging these into Heron's formula gives a long expression under the square root. Solving this part often requires a square root approximation.
Calculating area using approximations makes the answer more tangible, helping to visualize the triangle's area in a real-world context.
- First, evaluate the expression inside the square root: \( \sqrt{s(s-a)(s-b)(s-c)} \).
- For numerical results, calculate the square root using a calculator to simplify \( A \).
Calculating area using approximations makes the answer more tangible, helping to visualize the triangle's area in a real-world context.
Sides of a Triangle
Understanding the significance of a triangle's sides is crucial when applying formulas like Heron's. The lengths of sides play a decisive role in determining the shape and area of a triangle.
A triangle is defined by:
A triangle is defined by:
- Three sides, typically denoted as \( a \), \( b \), and \( c \).
- Heron's formula applies when all these side lengths are known, requiring no additional information about other triangle features like angles.