# Chapter 5 Lesson 5.3 Writing Linear Equations Given Two Points Worksheet

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5.3
5.3
Writing Linear Equations
Given Two Points
Goal
Write an equation of a
How steep is the mountain?
line given two points on
the line.
In this lesson you will learn
to write an equation of a line
Key Words
given any two points on the
• slope
line. In Example 1 you will
• slope-intercept form
write a linear equation that
• point-slope form
models a snowboarder’s
descent down a mountain.
Use a Graph
EXAMPLE
1
The line at the right models a
y
snowboarder’s descent down a
5
mountain. Write the equation
( 4, 5)
of the line in slope-intercept form.
3
(0, 2)
Student Help
Solution
1
x
Find
the slope.
S
T
TUDY
IP
1
7
5
3
1
In Example 1, notice
y
y
5
2
3
that the graph shows
2
1
m
x
x
4
0
4
the y-intercept.
2
1
Because you know the
Write
the equation of the line. From the graph, you can see the y-intercept
y-intercept, use the
is b
2. Use slope-intercept form.
slope-intercept form to
write the equation.
y
mx
b
Write slope-intercept form.
3
3
y
x
2
Substitute
for m and 2 for b.
4
4
3
The equation of the line is y
x
2.
4
Use a Graph
1.
The graph at the right
y
5
models a car’s ascent up a
hill. Write the equation of
(10, 4)
3
the line in slope-intercept
form.
(0, 1)
1
3
5
7
9
11
x
5.3 Writing Linear Equations Given Two Points
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