Lesson 8.1 Intro to Congruence

Task: Which figures are the same? Justify your answer. Please take 2 minutes to answer the question. There is no wrong or right answer. Picture 1 Picture 2 Picture 3 Picture 4

Congruent Figures (angles, sides, shapes) that are in identical form. Symbol: ≅ “=“ means same sizes and “~” means same shapes

There are 3 dimensions to describe the figures 1 dimension: line segments 2 dimensions: flat shapes (circle, square, triangle, etc) 3 dimensions: prisms (sphere, cylinders, cube, etc)

Three Essential Questions Describe how you can decide whether a pair of each of the following are congruent: line segments, angles, triangles, rectangular solids, cones, and cylinders. Can you use this test to determine whether two line segments are congruent? How can you adapt the test so that you can use it to determine whether three-dimensional objects such as spheres or rectangular boxes are congruent?

Translate these congruence statements into English sentences 1) ∆𝑇𝑅𝐼≅∆𝑀𝑇𝑉 “Triangle TRI is congruent to Triangle MTV”

Translate these congruence statements into English sentences 2) 𝑚<𝐴≅𝑚<𝐵 “measurement of angle A is congruent to measurement of angle B”

Translate these congruence statements into English sentences 3) 𝐴𝐵≅𝐶𝐷 “line segment AB is congruent to line segment CD”

Translate these congruence statements into English sentences 4) line 𝑙≅line 𝑟 “line l is congruent to line r "

To show 2 figures that have congruent sides

To show two figures that have congruent angles