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PRE-ALGEBRA
Lesson 1-10 Warm-Up
PRE-ALGEBRA
Lesson 1-10 Warm-Up
PRE-ALGEBRA
“The Coordinate Plane” (1-10)
What is the coordinate
plane and how do you
graph coordinates on
it?
coordinate plane (also called a grid): two number lines that intersect (cross)
at right angles
x-axis: the horizontal number line
y-axis: the vertical number line
origin (means “beginning”): the point at which the two number lines cross
quadrant (means “one of four parts”): one of the four sections made by the
intersection of the two axes
ordered pair: two numbers called the x-coordinate and y-coordinate that that
identify the location of a point on the coordinate plane
The x-coordinate tells you how far to move right (+) or left (-) from the origin
and the y-coordinate tells you how far to move up (+) or down (-) from the
origin.
PRE-ALGEBRA
The Coordinate Plane
LESSON 1-10
Additional Examples
Identify the coordinates of each point.
a. A
Point A is 2 units to the right of the y-axis.
The x-coordinate is 2.
Point A is 3 units below the x-axis.
The y-coordinate is –3.
The coordinates of point A are (2, –3).
b. B
Point B is 2 units to the left of the y-axis. The x-coordinate is –2.
Point B is 1 unit above the x-axis. The y-coordinate is 1.
The coordinates of Point B are (–2, 1).
PRE-ALGEBRA
The Coordinate Plane
LESSON 1-10
Additional Examples
1
2
Graph point P(–3, 2 ) on a coordinate plane.
PRE-ALGEBRA
“The Coordinate Plane” (1-10)
How do you name a
point on a grid?
Always start at the origin. Then, count the number of units (jumps) right (+) or
left (-) to identify the x – coordinate. From there, count the number of units up
(+) or down (-) from the x-axis to identify the y – coordinate
Example: Name the following coordinate.
Start at the origin. Move 2 units to the left (x = -2). Then move 3 units down
(y = -3). The coordinates of z are (-2, -3)
How do you graph a
point on a grid?
Example:
PRE-ALGEBRA
The Coordinate Plane
LESSON 1-10
Additional Examples
In which quadrant or on which axis would you find each point?
a. (5, 3)
Since the x-coordinate is positive and the y-coordinate
is positive the point is in Quadrant I.
b. (0, –7)
Since the x-coordinate is 0, the point is on the y-axis.
PRE-ALGEBRA
The Coordinate Plane
LESSON 1-10
Additional Examples
Graph a figure with vertices M(–3, 3), N(–3, –2),
P(1, 3), and R(1, –2). Name the figure.
Plot and label each point on a coordinate
plane. Connect the points with lines.
The figure is a rectangle.
PRE-ALGEBRA
The Coordinate Plane
LESSON 1-10
Lesson Quiz
Draw a coordinate grid. Graph each point.
1. S(2, 3)
2. T(2, –3)
3. U(–2, 3)
4. K(0, –3)
5. L(3, 0)
6. Graph a figure with vertices
A(–1, 4), B(3, 4), C(2, –1) and,
D(0, –1), Name the figure.
1–5
PRE-ALGEBRA