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Linear System of Simultaneous Equations Warm UP. First precinct: 6 arrests last week equally divided between felonies and misdemeanors. Second precinct: 9 arrests - there were twice as many felonies as the first precinct.
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Linear System of Simultaneous Equations Warm UP First precinct: 6 arrests last week equally divided between felonies and misdemeanors. Second precinct: 9 arrests - there were twice as many felonies as the first precinct. Write a system of two equations and find out how many felonies and misdemeanors occurred.
Sections 4.1 & 4.2 Matrix Properties and Operations
Matrix A matrix is any doubly subscripted array of elements arranged in rows and columns enclosed by brackets. Element
Row Matrix [1 x n] matrix
Column Matrix [m x 1] matrix
Square Matrix Same number of rows and columns Matrices of nth order -B is a 3rd order matrix
Identity Matrix Square matrix with ones on the diagonal and zeros elsewhere.
The Equal
Equal Matrices Two matrices are considered equal if they have the same dimensions and if each element of one matrix is equal to the corresponding element of the other matrix. = Can be used to find values when elements of an equal matrices are algebraic expressions
To solve an equation with matrices • 1. Write equations from matrix • 2. Solve system of equations • Examples • = • =
Linear System of Simultaneous Equations How can we convert this to a matrix?
Matrix Addition A new matrix C may be defined as the additive combination of matrices A and B where: C = A + B is defined by: Note: all three matrices are of the same dimension
Addition If and then
Matrix Subtraction C = A - B Is defined by
Subtraction If and then
Matrix Multiplication Matrices A and B have these dimensions: Video [r x c] and [s x d]
Matrix Multiplication Matrices A and B can be multiplied if: [r x c] and [s x d] c = s
Matrix Multiplication The resulting matrix will have the dimensions: [r x c] and [s x d] r x d
A x B = C [2 x 2] [2 x 3] [2 x 3]
A x B = C [3 x 2] [2 x 3] Result is 3 x 3 [3 x 2] [2 x 3] A and B can be multiplied [3 x 3]
Matrix Inversion Like a reciprocal in scalar math Like the number one in scalar math
Transpose Matrix Rows become columns and columns become rows