Download Coordinate Geometry

 Grid – A pattern of horizontal and
vertical lines, usually forming
squares.
What are the coordinates
for the house?
4,B
When we are
listing
coordinates; we
always state the
horizontal
coordinate first.
A
B
C
D
E
1 2 3 4 5
What are the coordinates
for the house?
(4,5)
State the
horizontal
coordinate first,
followed by the
vertical
coordinate
5
4
3
2
1
1 2 3 4 5
What are the coordinates
for the house?
(0,0)
This point is also
known as the
origin
5
4
3
2
1
1 2 3 4 5

x axis – a horizontal number
line on a coordinate grid.
0 1 2 3 4 5 6
x

x likes to lie down
horizontally.
0 1 2 3 4 5 6
x

y axis – a vertical number
line on a coordinate grid.
y
6
5
4
3
2
1
0

y likes to stand upright or
vertically.
y
6
5
4
3
2
1
0
 Coordinates – an ordered pair of
numbers that give the location of a
point on a grid.
(3, 4)
6
5
(3,4)
4
3
2
1
00 1 2 3 4 5 6
The first number is always the x.
 The second number is always the y.

6
5
(3,4)
4
3
2
1
00 1 2 3 4 5 6
 Step 1 – Always find the x value first,
by moving horizontally
y
(2, 3)
6
5
4
3
2
1
00 1 2 3 4 5 6 x
 Step 2 – Starting from your new
position find the y value by moving
vertically
y
(2, 3)
6
5
4
(2,3)
3
2
1
00 1 2 3 4 5 6 x
 Step 1 – Find how far over horizontally
the point is by counting along the x
axis
(5, )
y
6
5
4
3
2
1
00 1 2 3 4 5 6 x
 Step 2 – Now count how far vertically
the point is by counting along the y
axis
y
(5,4)
6
5
4
3
2
1
00 1 2 3 4 5 6 x
y
(3,5)
6
5
4
3
2
1
00 1 2 3 4 5 6 x
y
(2,6)
6
5
4
3
2
1
00 1 2 3 4 5 6 x
y
(4,0)
6
5
4
3
2
1
00 1 2 3 4 5 6 x
y
(0,5)
6
5
4
3
2
1
00 1 2 3 4 5 6x
y
(1,1)
6
5
4
3
2
1
00 1 2 3 4 5 6 x
 When
number lines are extended into
the negative number lines you add 3
more quadrants to the coordinate
y
grid.
3
2
1
x
0
-1
-2
-3
-3 -2 -1 0 1 2 3
 If the x is negative you move to
the left of the 0.
x = -2
y
3
2
1
x
0
-1
-2
-3
-3 -2 -1 0 1 2 3
 If the y is negative you move
down below the zero.
y
3
2
y=
1
0
x
-1
-2
-3
-3 -2 -1 0 1 2 3
-3
 Step 1 - Plot the x number first
moving to the left when the
number is negative.
y
3
2
(-3, -2)
1
x
0
-1
-2
-3
-3 -2 -1 0 1 2 3
 Step 2 - Plot the y number moving
from your new position down 2
when the number is negative.
y
3
2
(-3, -2)
1
x
0
-1
-2
-3
-3 -2 -1 0 1 2 3
 When x is positive and y is
negative, plot the coordinate in
this manner.
y
3
2
(2, -2) 1
0
x
-1
-2
-3
-3 -2 -1 0 1 2 3
 When x is negative and y is
positive, plot the coordinate in this
manner.
y
(-2, 2)
3
2
1
x
0
-1
-2
-3
-3 -2 -1 0 1 2 3
(-3, -3)
y
3
2
1
x
0
-1
-2
-3
-3 -2 -1 0 1 2 3
(-1, 2)
y
3
2
1
x
0
-1
-2
-3
-3 -2 -1 0 1 2 3
(1, -1)
y
3
2
1
x
0
-1
-2
-3
-3 -2 -1 0 1 2 3
(2, -2)
y
3
2
1
x
0
-1
-2
-3
-3 -2 -1 0 1 2 3
(-3, -2)
y
3
2
1
0
x
-1
-2
-3
-3 -2 -1 0 1 2 3
Ex 12A