# Lesson plan: Area of a Triangle

School:

Gulbaba Zeynep Yıldırım Yatılı Bölge Ortaokulu in Kilis, TR

Subject:

Mathematics

Topic:

Students will find the area of different Triangles.

Class:

Content:

Base is the side of a triangle. Base is the same as length. Height of a triangle forms a right angle with the base and extends to the highest point of the triangle.

Goals:

S1 problem solving: Student 2will build new mathematical knowledge through problem solving. S12 geometry: Student will specify location and describe spatial relationships using coordinate geometry and other representational systems. S3 measurement: Student will apply appropriate techniques, tool, and formula to determine measurements

Objectives:

Students will recognize and define three different triangles. Students will learn and apply the use the formula to find the area of a triangle.

Materials

Overhead projector or Dry Erase board, grid paper, pencil, overhead marker, triangle shapes and photos, math book, ruler

Introduction:

Explain that a parallelogram can be split in two triangle of equal area. What are the three triangle names and how are they different and similar? Why might you need to be able to figure out the area of these triangle? What career using this information? How is it applied to daily life?

Development:

Introduce the three types of triangles; obtuse, acute, and right. Review how to find the area of a rectangle. Use this to seg-way into finding the area of a triangle. Explain the formula; Area=.5(base)(height). Students will then work with different triangles and their measurements in order to find the area. Discuss why knowing how to find the area of a triangle is important. Help the students realize that a carpenter or architect will need to know this information.

Practice

Explain to the students they are now carpenters. Have them pair up and go around the classroom finding examples of the three types of triangles. Then they measure, with a ruler, each side of the triangle they found recording their results.

Accomodation

Pair students in such a manner that those needed extra guidance are with a student who excels in this subject area. Since the students will be roaming around the room the use of the classroom speaker system will be helpful to keep order and insure all of the students hear instructions.

Checking for understanding:

Students will complete pg. 441 in their textbooks.

Closure:

Evaluation:

Students will be evaluated on class and group participation. They will also be graded on the textbook page assignment.

Teacher reflections: