Unit 1-6: Operations with Matrices
How could we organize the data?
How would you organize the date?
Concept
Add and Subtract Matrices
Substitution
Add corresponding elements.
Simplify.
Answer:
Add and Subtract Matrices
Answer: Since the dimensions of A are 2 × 3 and the dimensions of B are 2 × 2, these matrices cannot be subtracted.
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Example 2
A.
B.
C.
D.
Concept
Example 3 Multiply a Matrix by a Scalar
Substitution
Example 3 Multiply a Matrix by a Scalar
Multiply each element by 2.
Answer:
Simplify.
Concept
Example 4 Multi-Step Operations
Perform the scalar multiplication first. Then subtract the matrices.
Substitution
Distribute the scalars in each matrix.
4A – 3B
Example 4Multiply.
Subtract corresponding elements.
Answer:
Simplify.
Multi-Step Operations
Example 4
A.
B.
C.
D.
Example 5 Use Multi-Step Operations with Matrices
BUSINESS A small company makes unfinished desks and cabinets. Each item requires different amounts of hardware as shown in the matrices.
DESK
Short LongNailsScrews
CABINET
Short
LongNailsScrews
The company has orders for 3 desks and 4 cabinets. Express the company’s total needs for hardware in a single matrix.
Example 5 Use Multi-Step Operations with Matrices
Write matrices.
Multiply scalars.
Add matrices.
Answer:
Example 5 Use Multi-Step Operations with Matrices
Write matrices.
Multiply scalars.
Add matrices.
Short LongNailsScrews
Answer:
AssignmentPg. 175-177#2,3,5,8,10,12,13,26,30,33