Algebra 1
Name:__________________
Day 7 Graphing Linear Equations in Slope-Intercept Form
Block:__________________
When an equation is in slope-intercept form it can be graphed on a set of axes.
Example #1 – Sketch a graph of each equation.
1
y   x2
2
3) y  6  x
y  3x  5
2
y   x 1
3
6) 4 x  2 y  6
(8)
y  3x
3
9) 𝑦 = 2 𝑥 − 3
8) y  4  x
10) 𝑦 = −4𝑥 + 5
11) 3x  3 y  6
12) 2 x  3 y  9
13) 𝑦 = −2𝑥
14) 2 x  y  5
(9)
Special Lines
There are two types of lines that are slightly different from the typical slant line. These lines are
horizontal, parallel to the x-axis, and vertical, parallel to the y-axis.
Horizontal Line
Vertical Line
Example #1 – The line y 3 is graphed on the grid at the right.
a) Graph and label the lines y 5 and y 2 on the same grid.
b) Label the coordinates of point A and B from the line y 3.
c) If it exists, find the slope of the line connecting points A and B
from above.
d) If it exits, find the y-intercept of the line connecting points A and B.
e) Write the equation of the line connecting A and B in y mx b form.
EQUATIONS OF HORIZONTAL LINES
y mx b where m 0 (or simply y b)
Example #2 – Which of the following represents the equation of the graph shown below?
(A) x 4
(C) y 4x
(B) y x 4
(D) y 4
(10)
Example #3 – The line x 2 is graphed on the grid at the right.
a) Graph and label the lines x 4 and x 3 on the same grid.
b) State the coordinates of point A and B from the line x 2.
c) If it exists, find the slope of the line connecting points A and B
from above.
d) If it exists, find the y-intercept of the line connecting points A and B.
e) Why is it not possible to write the equation of a vertical line in y mx b form?
EQUATIONS OF VERTICAL LINES
x a where a is the x intercept of the line
Example #4 – Graph the following three lines and find the area of the triangle enclosed by them.
Line #1 x 5
Line #2 y 3
Line #3 y 2x 1
Example #5 – Create a rough sketch and then write the equation of the line that fits each description:
a) parallel to the x-axis passing through 3, 2
b) parallel to the y-axis passing through 4, 3
(11)
Horizontal and Vertical Lines Practice
1. Which of the following equations represents the
line shown in the graph to the right?
(A) y 3
(B) x 3
(C) y 3x
(D) x 3y
2. Which of the following equations represents
the line shown in the graph to the right?
(A) y 2
(B) y 2x
(C) x 2
(D) y x 2
3. Graph and label the following two lines. Write the
coordinates of their intersection point.
x 5
y 4
4. Graph and label the following vertical and horizontal lines.

x  2
x4
y  3
y5






5. Graph and label the following lines.
Remember to solve for y in the equation of the slant line.
Line #1:
x 3
Line #2:
y 2
Line #3: 3y 2x 6
(12)
6. Which of the following represents the equation of the x-axis?
(A) x 1
(B) y 0
(C) y 1
(D) x 0
7. Which of the following represents the equation of a line that is parallel to the y-axis and passes through the
point (1, 4)?
(A) x 1
(B) y 4
(C) x 4
(D) y 1
8. Which of the following equations represents a line that is parallel to the x-axis and passes
through the
point 3, 5?
(A) x 3
(B) y 3
(C) x 5
(D) y 5
Homework
Directions: Graph each of the following equations. Then state the slope & y-intercept of each equation.
1. x  2
2. y  2
3. y  4
4. x  3.5
m=
m=
m=
m=
b=
b=
b=
b=
5. x  3
6. x  1
7. y  1
8. y  1.5
m=
m=
m=
m=
b=
b=
b=
b=
(13)
Directions: Write the equation for each of the given lines. Then determine the slope.
9.
10.
m=
13.
11.
m=
12.
m=
14.
15.
.
m=
16.
.
m=
m=
m=
m=
b=
b=
b=
b=
(14)