Graphs!
WEEK 3
–
JULY 22, 2018
BRANDY CHAMPION

Determining X & Y Intercepts!
•
The intercepts of a graph
are the points at which
the graph crosses the axes
–
ALWAYS equal ZERO!
•
The x-intercept is the point at
which the graph crosses the
x-axis
•
The y-coordinate is zero; ( x, 0 )
•
The y-intercept is the point at
which the graph crosses the
y-axis
•
The x-coordinate is zero; ( 0, y )
y-intercept
x-intercept

Determining X & Y Intercepts!
•
To determine the y-
intercept, set x = 0 and
solve for y.
•
y = 5(0) + 2
•
Solve!
•
y = 2
•
y-intercept is ( 0, 2 )
•
To determine the x-
intercept, set y = 0 and
solve for x.
•
0 = 5x + 2
•
Subtract 2:
•
-2 = 5x
OR
5x = -2
•
Divide by 5 on both sides:
•
x = -2/5
•
x-intercept is ( -2/5, 0 )
Example: y = 5x + 2
Confirm by graphing the equation!

Graphing Equations Using a Data Table or x &
y-intercepts!
•
y = 5x + 2
•
Only need TWO points to
graph a linear equation!
•
To create the table: Make
a list of x values and solve
for y.
x
-2
-1
0
1
2
y
x
-2
-1
0
1
2
y
-8
-3
2
7
12

Graphing Equations Using a Data Table!