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Video Check: Select all that apply with regards to the video embedded directly above this item.

Drag and drop to identify the mass of each box.
1 lb
2 lb
3 lb
4 lb
5 lb
6 lb
A Boxes
B Boxes
C Boxes
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Video Check: Select all that apply with regards to the video embedded directly above this item.
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Take Note: Systems of equations in three variables can be graphed in 3D as planes. Categorize each 3D graph on the left based on its number of solutions.
You may need to zoom out to see all of the items. You can also place each item from the left column by selecting it (click it) then selecting (clicking on) the category for it.

No Solution
One Solution
Infinite Number of Solutions

Problem 1 Got It?
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Video Check: Select all that apply with regards to the video embedded directly above this item.
Problem 2 Got It? What is the solution of the system? Use elimination.

Problem 2 Got It? Reasoning: Could you have used elimination in another way? Explain.
HINT: Could you have eliminated a different variable first?
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Video Check: Select all that apply with regards to the video embedded directly above this item.
Problem 3 Got It? What is the solution of the system? Use substitution.

-4
2
1
4
0
-2
x =
y =
z =

Problem 4 Got It?

🧠 Retrieval Practice:
Summarize the mathematical content of this lesson. What topics, ideas, and vocabulary were introduced?