Republic of the Philippines Department of Education Caraga Region XIII Surigao del Norte Division Mainit II District CANTUGAS CULTURAL NATIONAL HIGH SCHOOL Cantugas, Mainit, Surigao del Norte A Detailed Lesson Plan In GEOMETRY Grade 8 | 3rd Quarter I. Objectives : At the end of the lesson, students are expected to: a. complete the congruent marks to illustrate that the triangles are congruent through SSS Congruence Theorems; b. match the given sides of triangles to show that the triangles are congruent through SSS Congruence Postulate; c. describe the importance of equality in the society. II. Subject Matter Reference Skills Values : : : : SSS (Side-Side-Side) Congruence Postulate Mathematics Learner’s Module for Grade 8 page (357) drawing, analyzing and solving Unity and cooperation III. Materials : ruler, pencil, bond paper and cardboard IV. Procedure : 4A’s Method Teacher’s Activity A. Students Activity Preparation (prayer) (greetings) (announcing of classroom rules) (checking of attendance) (collecting of assignment) In the name of the Father,..........AMEN. Good morning Sir. Understand Sir. Present Sir. Done Sir. a. Review Before we proceed to our new lesson for today, let’s have first a review about our lesson last meeting. What did we discuss last meeting? Yes James Mark! Yesterday, we discussed about Congruence Postulate. Very Good! Now, who can recall what ASA Congruence Postulate is? Yes Hannah! ASA Congruence Postulate states that, “If the two angles and the included side of one triangle are congruent to the corresponding two angles and the included side of another triangle are congruent. Absolutely! Who wants to go to the board and illustrate the ASA Congruence Postulate? Go ahead Samjo! (student does as told) A X B C Y Very Good! The ∆ABC and ∆XYZ are congruent since ∠A is congruent to ∠X, side AC is congruent to side XZ and ∠c is congruent to ∠Z and it refers to ASA Congruence Postulate. b. Motivation Now class, I have here two triangles made from cardboard material. One is colored blue and the other one is colored yellow. Class do you know on how to determine the congruence of these two triangles colored blue and colored yellow by dealing only their sides not the angles? B. No, Sir! Activity So be with me this morning as I’ll discuss to you the “SSS Congruence Postulate.” Everybody read! “SSS Congruence Postulate” a. Statement of the Aim *complete the congruent marks to illustrate that the triangles are congruent through SSS Congruence Postulate; *match the given sides of triangles to show that the triangles are congruent through SSS Congruence Postulate: *describe the importance of equality in the society. Now, I’ll group you into 4 groups and form a circle with your group. All you have to do class is to draw the desired figure through the following procedures being flashed on the screen. Do you get me class? Yes Sir. When you are already finished, you have to say with action, “Clap, clap, clap Champion”! The group which can finish first will be the winner and will receive a secret price. I’ll give you five minutes to do it and your time starts now. Students do as told. Z Do the following in your group: 1. Draw a straight horizontal line segment and name it as ST having a length of 15cm. 2. On the point S of the line segment ST, draw a vertical line segment and name it as SU having a length of 20cm. 3. Connect the point U and T to form a new diagonal line segment named UT having a measure of 25cm. 4. Name the newly formed triangle as ∆STU and indicate the measures of the three sides of ∆STU. C. Analysis I want somebody from group 1 to draw their figure on the board. Yes Chievan! Student does as told. Is there somebody from group 2 to draw their figure on the board? Okay Emman! Student does as told. Is there any representative from group 3 to discuss the work of group 1? Kevin go ahead! Student does as old. How about from group 4 to discuss the work of group 2? Yes Antonnette! Student does as told. Great work everyone! U O Let’s name the other triangle as ∆OMN 25cm 25cm 20cm 20cm S T M 15cm What side of ∆STU corresponds with the side MO of ∆MNO? Yes Justin! Very good Justin. Since, sides MO and SU are corresponding sides, what then have you observed about their measures? Yes Danny! That’s right. N 15cm It is the side SU. SU and MO have the same measure. If they have the same measure, then how are we going to describe them? Yes Annie. That’s correct! The two sides are congruent. What side of ∆STU corresponds with the side MN of ∆MNO? Yes Katrice! Good job! How are you going to describe corresponding sides: MN and ST? Yes Ann! It is side ST. two MN and ST are corresponding and congruent sides because they have the same measure. Exactly! So now, how are you going to describe the last pair of sides; UT and NO? Yes Avegail! Absolutely! UT and NO are corresponding sides and they are also congruent because they have the same measures, both of which is 25cm.
