4.7 Identity and Inverse Matrices and Solving Systems of Equations Objectives: 1.Determine whether two matrices are inverses. 2.Find the inverse of a 2x2.

Slides:



Advertisements
Similar presentations
Determinant The numerical value of a square array of numbers that can be used to solve systems of equations with matrices. Second-Order Determinant (of.
Advertisements

Identity and Inverse Matrices
4.5 Inverses of Matrices.
Here is a preview of one type of problem we are going to solve using matrices. Solve this system of equations:
Matrix Revolutions: Solving Matrix Equations Matrix 3 MathScience Innovation Center Betsey Davis
Using Matrices to Solve a 3-Variable System
A Fast Introduction inverse matrix1 What is a matrix (One Matrix many matrices) Why do they exist Matrix Terminology Elements Rows Columns Square.
EXAMPLE 2 Solve a matrix equation SOLUTION Begin by finding the inverse of A = Solve the matrix equation AX = B for the 2 × 2 matrix X. 2 –7 –1.
Using Cross Products Lesson 6-4. Cross Products When you have a proportion (two equal ratios), then you have equivalent cross products. Find the cross.
Using Inverse Matrices Solving Systems. You can use the inverse of the coefficient matrix to find the solution. 3x + 2y = 7 4x - 5y = 11 Solve the system.
Using Matrices to Solve a System of Equations. Multiplicative Identity Matrix The product of a square matrix A and its identity matrix I, on the left.
Matrix Equations Step 1: Write the system as a matrix equation. A three-equation system is shown below.
3.5 Solution by Determinants. The Determinant of a Matrix The determinant of a matrix A is denoted by |A|. Determinants exist only for square matrices.
4.5 Solving Systems using Matrix Equations and Inverses.
4.4 & 4.5 Notes Remember: Identity Matrices: If the product of two matrices equal the identity matrix then they are inverses.
Inverses and Systems Section Warm – up:
4.5 Solving Systems using Matrix Equations and Inverses OBJ: To solve systems of linear equations using inverse matrices & use systems of linear equations.
4-7 Inverse Matrices & Systems
4-5 Matrix Inverses and Solving Systems Warm Up Lesson Presentation
Objectives Determine whether a matrix has an inverse.
Lesson 7.6 & 7.7 Inverses of a Square Matrix & Determinant.
1.10 and 1.11 Quiz : Friday Matrices Test: Oct. 20.
8.3 Another Way of Solving a System of Equations Objectives: 1.) Learn to find the inverse matrix 2.) Use the inverse matrix to a system of equations.
1. Inverse of A 2. Inverse of a 2x2 Matrix 3. Matrix With No Inverse 4. Solving a Matrix Equation 1.
Identity What number is the multiplication identity for real numbers? For matrices, n x n--square matrices, has 1’s on main diagonal and zeros elsewhere.
13.6 MATRIX SOLUTION OF A LINEAR SYSTEM.  Examine the matrix equation below.  How would you solve for X?  In order to solve this type of equation,
 1 is the multiplicative identify for real #’s : 1· a=a and a· 1 = a  For matrices n X n, the identity matrix has 1’s on its main diagonals and 0’s.
Chapter 4 Section 4: Inverse and Identity Matrices 1.
Warm-Up 3) Find the determinant by hand. 4) Find the determinant using your calculator. 1) Multiply. Show work. 2) Multiply. Show work.
Identity & Inverse Matrices
Inverse and Identity Matrices Can only be used for square matrices. (2x2, 3x3, etc.)
Have we ever seen this phenomenon before? Let’s do some quick multiplication…
Solving Equations Using Multiplication and Division Algebra 1 Section 3.2a.
One step equations Add Subtract Multiply Divide  When we solve an equation, our goal is to isolate our variable by using our inverse operations.  What.
4.7 Solving Systems using Matrix Equations and Inverses
4.8 Using matrices to solve systems! 2 variable systems – by hand 3 or more variables – using calculator!
GUIDED PRACTICE for Example – – 2 12 – 4 – 6 A = Use a graphing calculator to find the inverse of the matrix A. Check the result by showing.
2.5 Determinants and Multiplicative Inverses of Matrices. Objectives: 1.Evaluate determinants. 2.Find the inverses of matrices. 3.Solve systems of equations.
Warm up. Solving Systems Using Inverse Matrices Systems to Matrices A system of equations in standard form (Ax+By=C) can be written in matrix form [A][X]=[B]
Chapter 4 Section 5 and 6 Finding and Using Inverses Algebra 2 Notes February 26, 2009.
Use Inverse Matrices to Solve Linear Systems Objectives 1.To find the inverse of a square matrix 2.To solve a matrix equation using inverses 3.To solve.
3.8B Solving Systems using Matrix Equations and Inverses.
Warm Up Multiply the matrices. 1. Find the determinant. 2. –1 Welcome! I’m so glad you’re here! Please get your Calculator. Please get started on this.
Unit 1.11 – Use Inverse Matrices to Solve Linear Systems
Solving 2 step equations. Two step equations have addition or subtraction and multiply or divide 3x + 1 = 10 3x + 1 = 10 4y + 2 = 10 4y + 2 = 10 2b +
Using Matrices to Solve a 3-Variable System
College Algebra Chapter 6 Matrices and Determinants and Applications
Use Inverse Matrices to Solve Linear Systems
Daily Vocabulary Coefficient matrix Matrix of constants.
Ch. 7 – Matrices and Systems of Equations
Solving Equations: The Multiplication Principle
Using Determinants to solve systems of equations
Warm-Up BC 3. |A|.
Matrix Algebra.
Percent of Crop Grown in Each Country
Use Inverse Matrices to Solve Linear Systems
Solving Linear Systems Using Inverse Matrices
Find the inverse of the matrix
Use Inverse Matrices to Solve 2 Variable Linear Systems
Unit 3: Matrices
Inverse & Identity MATRICES Last Updated: October 12, 2005.
Inverse Matrices and Systems
3.8 Use Inverse Matrices to Solve Linear Systems
Solving Multiplication Equations
5 minutes Warm-Up Multiply Matrix A times Matrix B.
Bellwork 1) Multiply. 3) Find the determinant. 2) Multiply.
Solving simultaneous equations
1.11 Use Inverse Matrices to Solve Linear Systems
Solving Linear Systems of Equations - Inverse Matrix
Using Cross Products Chapter 3.
Presentation transcript:

4.7 Identity and Inverse Matrices and Solving Systems of Equations Objectives: 1.Determine whether two matrices are inverses. 2.Find the inverse of a 2x2 matrix 3.Write matrix equations for systems of equations 4.Solve systems of equations using matrix equations

Identity Matrix An identity matrix is a matrix that when multiplied by another matrix gives the same matrix back. (like multiplying a number by 1) The Diagonal from left to right contains only the number 1 and all other elements are 0.

Example of How the Identity Matrix works Multiply (you should get the same matrix back)

Inverses Two matrices are inverses if their products are the identity matrix. To determine if they are inverses, multiply the matrices to see if the product yields the identity matrix. Example: They are inverses.

Finding Inverses The inverse of 2x2 matrix is where ad-bc≠0

Example Find the inverse.

Using Matrices to solve Systems of Equations To solve a system using a matrix, use the inverse. For the system 5x+3y=13 4x+7y=-8 Create 3 matrices:

Continued Find inverse of coefficient matrix. Multiply this by the other side (what x and y are set = to). This is like dividing by what is being multiplied by the variable. Inv= multiply this by the other side so (5,-4)

Try One Solve using an inverse matrix. 3x+y=13 4x-2y=24

Homework p. 199, 10, 20, 26 p. 206, 20, 24, 28, 30