Lesson Plan Teknis | Area: Trapezoid

Objective

Duration: 10 - 15 minutes

This stage aims to ensure that students grasp the significance of calculating the area of a trapezoid and can use this knowledge in real-life situations, such as working out land area. This understanding is crucial for honing mathematical skills that are valuable in the job market, where accuracy and problem-solving skills are in high demand.

Objective Utama:

1. Understand the formula for the area of a trapezoid S = h(B + b) / 2.

2. Apply the formula to calculate the area of different trapezoids in practical problems.

Objective Sampingan:

1. Foster problem-solving skills in mathematics.
2. Encourage critical thinking and analytical skills when tackling real-life problems.

Introduction

Duration: 10 - 15 minutes

The aim of this stage is to ensure that students recognize the importance of calculating the area of a trapezoid and can effectively apply this knowledge in practical scenarios, like identifying land area. This comprehension is vital for developing mathematical skills relevant in the job market, where accuracy and problem-solving capabilities are crucial.

Curiosities and Market Connection

Did you know that civil engineers apply the formula for the area of a trapezoid to estimate the amount of materials required to construct roads and bridges? Surveyors also rely on this formula to measure irregularly shaped land, ensuring that every square centimeter is accurately accounted for. Architects use this knowledge too, to create functional and efficient designs.

Contextualization

Trapezoids are shapes that we often encounter around us, like in land plots, roofs of houses, and even in the design of some bridges. Knowing how to calculate the area of a trapezoid is fundamental for various careers, including civil engineering, architecture, and surveying, where it's essential to determine the area of irregular surfaces for effective planning and construction.

Initial Activity

Short Video: Show a 2-3 minute video highlighting real-world examples of trapezoid applications in industries, especially in construction and architecture. Provocative Question: Pose the question: 'How do you think professionals find out the materials needed to construct a bridge?'. Allow students some time for thought and then let them discuss their ideas in pairs.

Development

Duration: 50 - 60 minutes

The goal of this stage is to solidify students' grasp of the trapezoid area formula through engaging and practical activities. By constructing and measuring a trapezoid, students will develop precision skills and relate theoretical knowledge to real-world situations. The fixation exercises will provide practice opportunities to reinforce their learning effectively.

Topics

1. Definition of trapezoid and its properties

2. Formula for the area of a trapezoid: S = h(B + b) / 2

3. Real-life application of the formula in problems

Thoughts on the Subject

Encourage students to reflect on the relevance of area calculations in day-to-day life. Ask them how building a house or measuring a plot would pan out without accurately applying mathematical formulas. Prompt them to consider the precision needed in careers like engineering and architecture, and how miscalculations could lead to wastage of resources.

Mini Challenge

Maker Challenge: Constructing a Mini Plot

In this activity, students will create a mini land plot using materials like cardboard, a ruler, and scissors. They will sketch and cut out a trapezoid, measure its bases and height, and compute its area using the formula they learned.

1. Divide students into groups of 3-4.

2. Provide materials: cardboard, ruler, scissors, pencil, and calculator.

3. Instruct each group to draw a trapezoid on the cardboard with random measurements for the bases (B and b) and the height (h).

4. After drawing, students should carefully cut out the trapezoid.

5. Students will then measure the bases and height using the ruler.

6. Using the formula S = h(B + b) / 2, students will calculate the trapezoid's area.

7. Each group should present their trapezoid, explaining the measurements used and how they calculated the area.

Apply the area formula of a trapezoid in practice, enhancing skills in measurement, calculation, and teamwork.

**Duration: 30 - 40 minutes

Evaluation Exercises

1. Calculate the area of a trapezoid with bases measuring 8 cm and 5 cm, and a height of 6 cm.

2. A piece of land is shaped like a trapezoid with bases measuring 12 m and 7 m, and a height of 10 m. What is the area of this land?

3. An architect needs to find the area of a trapezoidal roof to estimate the needed amount of tiles. The bases of the roof measure 15 m and 10 m, with a height of 4 m. What is the area of the roof?

Conclusion

Duration: 10 - 15 minutes

The aim of this stage is to reinforce learning, allowing students to contemplate what they have absorbed and how they put their knowledge into practical use. The discussion and content recap strengthen understanding, while the link to real applications underscores the topic's relevance in daily living and future career paths.

Discussion

Facilitate a dialogue among students regarding how the trapezoid area formula was applied throughout the lesson and its real-life implications. Invite students to share their experiences from the maker challenge and their thoughts on applying theory during hands-on activities. Prompt them to consider how this knowledge might benefit their lives and future careers.

Summary

Reiterate the key points of the lesson, emphasizing the definition and properties of a trapezoid, the area formula S = h(B + b) / 2, and the application of this formula in real-world contexts. Remind students of the steps taken in the mini maker challenge, from constructing the trapezoid to calculating its area, as well as the importance of teamwork and precision.

Closing

Discuss how the lesson blended mathematical theory with practice and its relevance to the job market. Highlight the significance of being able to calculate the area of a trapezoid in professions such as engineering, architecture, and surveying. Conclude by stressing that mathematical problem-solving skills and the ability to relate theory to real-life situations are essential for academic and professional success.