5-2 Using Intercepts
Activating Prior Knowledge – Notes
Solve each equation.
1. 5x + 0 = –10
3. 0 + 2y = 14
–2
7
2. 33 = 0 + 3y
4. 0 – 5y = 5
11
-1
Tie to LO
5-2 Using Intercepts
Learning Objective
Today, we will
find x- and yintercepts.
CFU
5-2 Using Intercepts
Concept Development
– Notes #1 & 2
1. A y-intercept is the
y-coordinate of any
point where a graph
intersects the y-axis.
2. The x-coordinate of
this point is always 0.
CFU
5-2 Using Intercepts
Concept Development
– Notes #3 & 4
3. An x-intercept is
the x-coordinate of
any point where a
graph intersects the
x-axis.
4. The y-coordinate of
this point is always 0.
CFU
5-2 Using Intercepts
Skill Development – Notes #5
Find the x- and y-intercepts.
The graph intersects the
y-axis at (0, 1).
The y-intercept is 1.
The graph intersects the
x-axis at (–2, 0).
The x-intercept is –2.
CFU
5-2 Using Intercepts
Skill Development – Notes #6
Find the x- and y-intercepts.
The graph intersects the
y-axis at (0, 3).
The y-intercept is 3.
The graph intersects the
x-axis at (–2, 0).
The x-intercept is –2.
CFU
5-2 Using Intercepts
Skill Development – Notes #7
Find the x- and y-intercepts.
5x – 2y = 10
To find the x-intercept,
To find the y-intercept,
replace y with 0 and solve replace x with 0 and solve
for x.
for y. 5x – 2y = 10
5x – 2y = 10
5x – 2(0) = 10
5(0) – 2y = 10
5x – 0 = 10
5x = 10
0 – 2y = 10
–2y = 10
x=2
The x-intercept is 2.
y = –5
The y-intercept is –5.
CFU
5-2 Using Intercepts
Skill Development – Notes #8
Find the x- and y-intercepts.
–3x + 5y = 30
To find the y-intercept,
To find the x-intercept,
replace y with 0 and solve replace x with 0 and solve
for y. –3x + 5y = 30
for x. –3x + 5y = 30
–3(0) + 5y = 30
–3x + 5(0) = 30
0 + 5y = 30
–3x – 0 = 30
5y = 30
–3x = 30
x = –10
The x-intercept is –10.
y=6
The y-intercept is 6.
CFU
5-2 Using Intercepts
Skill Development – Notes #9
Find the x- and y-intercepts.
3x - 2y = 12
To find the x-intercept,
To find the y-intercept,
replace y with 0 and solve replace x with 0 and solve
for x.
for y. 3x - 2y = 12
3x - 2y = 12
3(0) - 2y = 12
3x - 2(0) = 12
0 - 2y = 12
3x – 0 = 12
-2y = 12
3x = 12
−2𝑦 12
3𝑥 12
=
=
−2
−2
3
3
y = -6
x=4
The x-intercept is 4.
The y-intercept is -6.
CFU
5-2 Using Intercepts
Closure – Notes
1. What did we learn today?
2. Why is this important to you?
3. How do you find the x- and y- intercepts?
4. Find the x- and y-intercepts.
a. -3x + 5y = 30
b. 4x + 2y = 16
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