Five-Minute Check (over Lesson 2–3)
CCSS
Then/Now
New Vocabulary
Key Concept: Slope-Intercept Form
Example 1: Write an Equation in Slope-Intercept Form
Key Concept: Point-Slope Form
Example 2: Write an Equation Given Slope and One Point
Example 3: Standardized Test Example
Key Concept: Parallel and Perpendicular Lines
Example 4: Write an Equation of a Perpendicular Line
Over Lesson 2–3
Find the rate of change for the data.
A. –22 mi/gal
B.
C.
mi/gal
mi/gal
D. 22 mi/gal
Over Lesson 2–3
Find the slope of the line that passes through
points (2.3, 9.5) and (3.8, 20).
A. –7
B.
C. 7
D.
Over Lesson 2–3
Find the slope of the line that passes through
points (3, 5) and (–6, 5).
A. –1
B. 0
C. 1
D. 3
Over Lesson 2–3
Determine the rate of change of the graph.
A. –3
B.
C.
D. 3
Over Lesson 2–3
A. 72 cm
B. 108 cm
C. 432 cm
D. 648 cm
Content Standards
A.SSE.1.b Interpret complicated expressions
by viewing one or more of their parts as a
single entity.
A.CED.2 Create equations in two or more
variables to represent relationships between
quantities; graph equations on coordinate
axes with labels and scales.
Mathematical Practices
2 Reason abstractly and quantitatively.
You determined slopes of lines.
• Write an equation of a line given the slope
and a point on the line.
• Write an equation of a line parallel or
perpendicular to a given line.
• slope-intercept form
• point-slope form
• parallel
• perpendicular
Write an Equation in Slope-Intercept Form
Write an equation in
slope-intercept form for the line.
Step 1
Find the slope.
•
•
Slope formula
(x1, y1) = (–1, 4), (x2, y2) = (2, 3)
Simplify.
Write an Equation in Slope-Intercept Form
Step 2
Use the slope and a point to find the
y-intercept.
Slope-intercept form
Simplify.
The y-intercept is
Write an Equation in Slope-Intercept Form
Step 3
Substitute the values into the slope-intercept
equation.
Slope-intercept form
Write an equation in slopeintercept form for the line.
A.
B.
C.
D.
Write an Equation Given Slope and One Point
Point-slope form
Simplify.
Write an Equation Given Slope and One Point
Subtract 2 from each side.
Answer:
A.
B.
C.
D.
What is an equation of the line through (2, –3) and
(–3, 7)?
A
B
C
D
Read the Test Item
You are given the coordinates of two points on the line.
Solve the Test Item
Step 1
Find the slope of the line.
Slope formula
(x1, y1) = (2, –3), (x2,y2) = (–3, 7)
Simplify.
The slope is –2. That eliminates choices B and C.
Step 2
Write an equation. Use either ordered pair
for (x1, y1).
Point-slope form
m = –2; (x1, y1) = (2, –3)
Simplify.
Subtract 3 from each side.
Answer: D
Which is an equation of the line that passes
through (2, 5) and (–1, 3)?
A.
B.
C.
D.
Write an Equation of a Perpendicular Line
Write an equation in slope-intercept form for
the line that passes through (3, –2) and is
perpendicular to the line whose equation is
y = –5x + 1.
Write an Equation of a Perpendicular Line
Point-slope form
Distributive Property
Subtract 2 from each side.
Answer:
A.
B.
C.
D.