Solving Systems of Linear Equations

Use substitution to solve the following linear system:

x+3y=12

2x+y=6

• (1.2, 3.6)

• (1,5)

• (2,7)

• (5.7, 2.4)

What is the solution to this system?

• (1, -1)

• (-1, 1)

• (0, -2)

• (0, 1)

How many solutions does this system have?

• One Solution

• No solution

• Infinitely Many Solutions

Solve the system of equations by graphing.

• (2, 1)

• No Solution

• Infinitely Many Solutions

• (1, 2)

Solve the system of equations by graphing.

• (-4, 1)

• (4, -1)

• (4, 5)

• (5, 4)

The solution to a system of equations is any ordered pair that makes both equations true. 

• TRUE
• FALSE

What is the solution?

• One Solution
• No solution
• Infinitely Many Solutions

Solve this system by substitution.

• (1, -4)

• (1, 4)

• (-4, -7)

• (-7, -4)

The solution (x, y) to a system of equations is the point where they...? 

• Run off the graph
• Don't touch
• Intersect
• Exist

What variable do you eliminate?

4x + 8y = 20

−4x + 2y = −30

• X because they have opposite signs

• Y because they have opposite signs