1. Multiplying Matrices

2. Review: Scalar Multiplication

3. **You can only multiply two matrices if the number of columns in the 1 st matrix is equal to the number of rows in the 2 nd matrix. Dimensions: 3 x 2 2 x 3 They must match. The dimensions of your answer.

4. Examples: 2(3) + -1(5)2(-9) + -1(7)2(2) + -1(-6) 3(3) + 4(5) 3(-9) + 4(7)3(2) + 4(-6)

5. Dimensions: 2 x 3 2 x 2 *They don’t match so can’t be multiplied together.*

6. 2 x 2 2 x 2 *Answer should be a 2 x 2 0(4) + (-1)(-2)0(-3) + (-1)(5) 1(4) + 0(-2) 1(-3) +0(5)

7. The Salem youth baseball and softball leagues charge the following registration fees: ages 7-8, $45; ages 9-10, $55; and ages 11-14, $65 1)Write a matrix for the registered fees and a matrix for the number of players. 2)Find the total amount of money the league received from baseball and softball registrations. Team Members AgeBaseballSoftball 7-8350280 9-10320165 11-14180120

8. Carmen Fox owns three fruit farms on which he grows apples, peaches, and apricots. He sells apples for $22 a case, peaches for $25 a case, and apricots for $18 a case. # of Cases in Stock of Each Type of Fruit FarmApplesPeachesApricots 1290165210 2175240190 3110750 1)Write an inventory matrix for the number of cases for each type of fruit for each farm. 2)Write a cost matrix for the price per case for each type of fruit. 3)Find the total income of the three fruit farms expressed as a matrix. 4)What is the total income from all three fruit farms combined?