Systems Substitution

What is the first step in solving a system by Substitution?

• Make sure both equations are in standard form.

• Make sure at least one equation is solved for one variable.

• Make sure both equations are in slope-intercept form.

• Make sure both equations can be solved.

Which best describes a solution to a system of equations?

How do you know when a system is ready for substitution?

• You just guess

• All the variables "line up"

Solve the system.

The x - coordinate is ​​ (a)   .

The y - coordinate is ​ (b)   .

• 2

• 11

• -11

• -2

• 0

• 4

Use substitution to find the x-coordinate of the solution.

• No solution

• -6

• 6

• Many solutions

What is the solution to this system? Solve by substitution.
y= 4x + 3
2x - 3y = 21

• (3,-9)

• (-3,-9)

• (-3,9)

• (0,1)

Solve the system using substitution. ​

x=​ ​ (a)  

y=​ ​ (b)  

• -1

• 2

• -3

• -2

• 3

• 5

• A
• B
• C
• D

Solve the system.

The x - coordinate is ​ (a)  

The y - coordinate is ​ (b)  

• 4

• 3

• -11

• -2

• 0

• 2