http://www.ck12.org Chapter 8. Systems and Matrices
K=
144 192
115 127
27 34
a. What does 127 represent?
b. How many muffins did Kate sell in total?
c. How many bagels did Kate sell in her first location?
d. Which location is doing poorly?Solution:
a. 127 represents the number of muffins that Kate sold in her second location. You know this because it is in the
muffin column and the second row.
b. The total muffins sold is equal to the sum of the right hand column. 192+ 127 + 34 = 353
c. Kate sold 144 bagels at her first location.
d. The third location is doing much worse than the other two locations.Example C
Identify the order of the following matrices
A=[1 3 4 7], B=
[21 45 1
34 1 5
]
, C=
25 235
562 562
4 413
454 33
1 141
Solution: Ais 1×4,Bis 2×3,Cis 5×2. Note that 4× 1 , 3 × 2 , 2 ×5 are not the same orders and would be
incorrect.
Concept Problem Revisited
By writing every hollow square as a 0 and a blank square as a 1 a computer could read the picture:
When you use computers to manipulate images, the computer just manipulates the numbers. In this case, if you
swap zeros and ones, you get the negative image.