Chapter 7 Coordinate Geometry

Notes

Coordinate Geometry:

Study of points on graph

Uses x-axis and y-axis

Cartesian Plane:

Horizontal line = x-axis

Vertical line = y-axis

Meeting point = origin (0,0)

Quadrants:

First quadrant → (+,+)

Second quadrant → (-,+)

Third quadrant → (-,-)

Fourth quadrant → (+,-)

Distance Formula:

d=

(x

2

​

−x

1

​

)

2

+(y

2

​

−y

1

​

)

2

​

-10

-8

-6

-4

-2

2

4

6

8

10

-10

-5

5

10

A(6.0, 6.0)

B(-6.0, -6.0)

d = 16.97

Delta x = 12

Delta y = 12

Midpoint Formula:

(

2

x

1

​

+x

2

​

​

,

2

y

1

​

+y

2

​

​

)

-10

-8

-6

-4

-2

2

4

6

8

10

-10

-5

5

10

A(-7.0, -3.0)

B(5.0, 7.0)

M = (-1.0, 2.0)

Section Formula:

(

m+n

mx

2

​

+nx

1

​

​

,

m+n

my

2

​

+ny

1

​

​

)

Important points:

On x-axis → y = 0

On y-axis → x = 0

Origin = (0,0)

Common mistakes:

Sign mistakes

Wrong subtraction

Confusing quadrants

Forgetting square root