Solving a System of Equations using Substitution

Solving Systems of Equations using Substitution

GOAL: Students will be able to solve a system of equations using substitution.

Poll

How confident are you are solving a system of equations using substitution?

• I am rock SOLID!

• I am probably ok, but a few more examples wouldn't hurt.

• I still have a lot of questions.

• I will need help walking through that again.

Multiple Choice

What does

"solution to a system of equations"

mean?

• It's the point where both equations equal zero

• It's the point where graphs of both equations cross the y-axis

• It's the point that solves both equations at the same time

• It's the point where graphs of both equations cross the x-axis

Multiple Choice

The first step in solving using the substitution method is __________.

• get x by itself

• get y by itself

• get either variable by itself

• add the equations together

Multiple Choice

Solve the system by substitution. 
3x − 2y = 7 
y = 2x − 7 

• No solution 
•  (7, 7)  
•  (−7, −7)  
•  (−7, −3)  

Multiple Choice

Solve the system by substitution. 
y = 2x − 11 
2x − 8y = 4 

•  (6, 1)
• (6, −4)
• (6, −1)
• Infinite number of solutions  

Multiple Choice

Solve this system of equations.

y = 2x + 1

y = 4x - 1

• (1,3)

• (-1,-3)

• (-1,3)

• (3,1)

Multiple Select

What are ALL the possible solutions to a System of Equations?

• One Solution

• Infinite Solutions

• No Solution

Poll

Now that you have had a bit more practice and review, how confident are you at solving a system of equations using substitution?

• I am rock SOLID!

• I am probably ok, but a few more examples wouldn't hurt.

• I still have a lot of questions.

• I will need help walking through that again.