# Ordered Pairs, Intercepts, And Slopes Worksheet Page 9

Secton . — Ordered Pars, Intercepts, and Slopes

A
e
c
ddressing
ommon
rrors
Incorrect
Correct
Issue
Resolution
Validation
Process
Process
Given the points
P
= (1, 3)
Switch the points and
Reversing
While either
1
coordinate
point can be P
,
(1, 3) and (2, 7),
recalculate:
P
= (2, 7)
1
values
it is critical that
2
calculate the slope of
P
= (2, 7), P
= (1, 3)
when using
you preserve
(
y
-
y
)
1
2
their line.
m
=
the Slope
that order when
2
1
(
y
-
y
)
(
x
-
x
)
m
=
2
1
Formula
substituting
2
1
x
-
x
(
)
values into the
-
2
1
(
7 3
)
(
7 3
-
)
m
=
Slope Formula. If
(
3 7
-
)
m =
(
2 1
-
)
m
=
-
(
1 2
)
you find yourself
(
1 2
-
)
making this
4
4
slope
=
=
4
error, consider
-
4
slope
= - = -
4
1
slope
=
=
4
1
labeling the
-
1
points P
and P
1
2
them straight.
Find the y-intercept:
Find the y-intercept:
You must substitute
Reporting a
Remember that
y-intercept
the intercepts
both the x- and y-
x + 4y = 12
x + 4y = 12
as only a y-
are points, and
values for any point,
value rather
therefore consist
including intercepts,
than an
of both an x- and
Let x = 0
Let x = 0
when validating your
ordered pair
y-value, even
0 + 4y = 12
0 + 4y = 12
work.
when that value
is zero.
y = 3
y = 3
?
(0) + 4(3)
= 12
The y-intercept is
The y-intercept is 3.
12 = 12 
(0, 3).
If the x-coordinate
If the x-coordinate
Substitute the ordered
Confusing
Solutions to
the x- and y-
equations are all
is 3, what is the
is 3, the ordered
pair values into the
coordinates
ordered pair solution
pair will be (3, y).
original equation:
in an ordered
always associate
for the equation
We must determine
pair
x with the first
x – y = 5
x – y = 5?
the value of y.
coordinate value:
?
(x, y).
x y
- =
(3) – (–2)
= 5
5
?
3
- =
y
5
x – 3 = 5
3 + 2
= 5
3 3
- - = -
y
5 3
x = 8
5 = 5 
- =
y
2
(8, 3)
( )(
-
1
-
y
) ( )
= -
1 2
y
= -
2
The ordered pair
solution is (3, –2).