Intro to Algebra
Name: _______________________________
Unit 2: Lesson 2.2c
Date: _________________ Period: _______
Similar Triangles and Slope
Essential Question:
How can slope of a line be used to describe the line?
Goal: I will be identify similar right triangles while using slope.
Key Ideas/Vocabulary:
 Similar Right Triangles – two rights triangles that have corresponding leg lengths that are
________________.
Section 1: Preparing for the Lesson
1) Refer to the graph at the right.
____________a. Find the slope of the line.
____________b. What geometric figure is formed by
connecting the vertices (0, 2), (0, 4),
and (3, 4)?
____________c. What geometric figure is formed by
connecting the vertices (6, 6), (6, 8),
and (9, 8)?
____________d. How do the two figures you identified in Exercises 3 and 4 relate
to each other?
____________e. What geometric figure is formed by connecting the vertices (0, 2),
(0, 6), and (6, 6)?
____________f. How do the two figures you identified in Exercises 3 and 5 relate
to each other?
Section 2: Similar Triangles and Slope
2) For each graph,
a. Find the slope of each line.
b. Find the length of the vertical and horizontal side lengths of each
triangle shown.
c. Find the simplified ratio of the vertical side length to the horizontal side
length and explain how this ratio relates to the slope of the line.
#1
#2
Answers:
a.)___________________________________b.)__________________________c.)_________________
a.)___________________________________b.)__________________________c.)_________________
YT 2) For each graph,
a. Find the slope of each line.
b. Find the length of the vertical and horizontal side lengths of each triangle shown.
c. Find the simplified ratio of the vertical side length to the horizontal side length and
explain how this ratio relates to the slope of the line.
#1
#2
#3
#4
Answers:
a.)___________________________________b.)__________________________c.)_________________
a.)___________________________________b.)__________________________c.)_________________
a.)___________________________________b.)__________________________c.)_________________
a.)___________________________________b.)__________________________c.)_________________
Section 3: Common Core Review
3) Which of the following statements is NOT true
concerning the graph below?
Answer:
A.) The simplified ratio of the vertical side length
to the horizontal side length of each triangle is 1.
B.) The slope of the line is 1.
C.) The slope of the line is -1.
D.) The smaller triangle and the larger triangle
shown are similar.
YT 3) Which statement is TRUE concerning the
slope of the line below?
Answer:
A.) It is equivalent to the simplified ratio of the
vertical side length to the horizontal side length of
each triangle shown.
B.) It is equivalent to
3
.
2
C It is equivalent to the simplified ratio of the
horizontal side length to the vertical side length of
each triangle shown.
2
3
D It is equivalent to  .
Homework:
Unit 2 – Practice Quiz 1
Lesson summary: The slope of a line is -3.5. What is the simplified ratio of the vertical side length to the
horizontal side length of each triangle formed?