GRAPHING SYSTEMS OF EQUATIONS

Chapter 3 Section 1

Systems of Equations

System of Equations: a group of 2 or more lines graphed on the same coordinate plane Ax + By = C ----------- Equation 1 Dx + Ey = F ----------- Equation 2

Solution: the solution to the system is the point (x, y) where the 2 equations/lines intersect

Two exceptions: Parallel Lines: No solutions – the lines never

intersect Same line: IMS- The lines intersect everywhere

Visual representations

1 solution:

No Solution:

IMS:

Steps

1.) Graph the first equation on the coordinate plane

2.) Graph the second equation on the same coordinate plane

3.) Find the point where the 2 lines intersect- or determine if they are the same/parallel lines

4.) Check if the point works in both equations

Examples

1.) y = -x + 3 2x -3y = 1

Examples

2.) 2x -2y = -8 2x + 2y = 4

Examples

3.) 3x -2y = 6 6x – 4y = 12

Examples

4.) 3x – 2y = 6 3x – 2y = 2

Pros and cons about graphing

Visual Tedious/Precious/Neat Predictions Fractions- answers? Time consuming

Classwork

Pg 142 # 4-6, 7-9, 10

Cell phones

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