1. Sec 7: Solving Systems of Equations with Matrices
Homework: Pg 195 #39-47, 55a
Sec 7: Solving Systems of Equations with Matrices
Learning Target: I will solve systems of equations in mathematical and real-world situations using matrices.

2. Review: Quality Core Practice

3. Ex 1: The Identity Matrix
Multiply the following matrices:
a −4 1 =
b − − =
What happened when you multiplied a matrix by the Identity Matrix?

4. Watch the KornKast video and take notes here.
Generic Example
Example with Numbers

5. Ex 2: Write each system as a matrix equation and solve.
A B.

6. Ex 3: Shopping!
A linen shop has several tables of sheets and towels on special sale. The sheets are all priced the same and so are the towels. Mario bought 3 sheets and 5 towels at the cost of $ Marco bought 4 sheets and 2 towels at the cost of $ Find the price of each item.

7. Ex 4: Happy Holidays!
Suppose you want to fill nine 1-lb tins with a holiday snack mix. You plan to buy almonds for $2.45/lb, peanuts for $1.85/lb and raisins for $.80/lb. You have $15 and want the mix to contain an equal amount of nuts to raisins. How much of each ingredient should you buy?

8. Constructed Response Tomorrow!
HOMEWORK
Pg 195 #39-47, 55a - due Friday if we don’t finish the notes today.
*Use inverse matrices to solve each system of equations.
Constructed Response
Tomorrow!