Suggested languages for you:

Americas

Europe

Q7Q

Expert-verified
Found in: Page 93

### Linear Algebra and its Applications

Book edition 5th
Author(s) David C. Lay, Steven R. Lay and Judi J. McDonald
Pages 483 pages
ISBN 978-03219822384

# If a matrix $$A$$ is $${\bf{5}} \times {\bf{3}}$$ and the product $$AB$$is $${\bf{5}} \times {\bf{7}}$$, what is the size of $$B$$?

$$3 \times 7$$

See the step by step solution

## Step 1: Find the number of rows of matrix $$B$$

Since the matrix $$A$$ has three columns, the number of rows in the matrix $$B$$ must be three.

## Step 2: Find the number of columns of matrix $$B$$

The number of columns in matrix $$AB$$ is seven, then the number of columns in matrix $$B$$ is seven.

So, the size of matrix $$B$$ is $$3 \times 7$$.