Math 9, Lesson 10, Fall Semester 2016, 11/20/2016

Weidong Posted in Fall 2016, Homework, Teaching info
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We start a new topic today. We study matrices.

In real life, we often use tables to help organize data. If we abstract the concept by extracting the data from a table and arrange them in a rows and columns with brackets, we call this rectangular array of numbers a matrix. The numbers in a matrix are called entries or elements. An element is identified by its row and column positions in the matrix. If a matrix has m rows and n columns, we say that the order of this matrix is m x n. A matrix having the same number of rows and columns is called a square matrix. For a square matrix, we can simply say its order with the number of rows.

We usually use capital letters to represent matrices.

Two matrices A and B are equal, written as A = B, if they have the same order and their corresponding elements are equal.

We then discuss the addition and subtraction of two same-order matrices.

If A and B are two matrices of the same order, then sum A+B is the matrix obtained by adding the corresponding elements in A and B.

Similarly, we define subtraction of two same-order matrices.

We talk about zero matrix where all elements are zero. It is often represented  as O.

Homework:

Page 1, Page 2, Page 3, Page 4, Page 5, Page 6, Page 7, Page 8 (please keep these pages, we will need them for the next two lessons)

Workbook Page 19, #1 – #6, #12, #14, #16

Answers to last week’s homework: Answers

Note, there is no school next Sunday on 11/27. Have a nice Thanksgiving Holiday!

Math 9, Lesson 9, Fall 2016, 11/13/2016

Weidong Posted in Fall 2016, Homework, Teaching info
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We went over the midterm exam first, then did a review on equations and inequalities.

We looked at linear equations, system of linear equations, quadratic equations, rational equations, and linear inequalities.

For homework, use the sheets below:

#2 – #18.

Page 1Page 2Page 3

Math 9, Lesson 8, Fall 2016, 11/6/2016

Weidong Posted in Fall 2016, Teaching info
Comments Off on Math 9, Lesson 8, Fall 2016, 11/6/2016

We have mid term exam today. I will have the test results ready next week.