Posts Tagged ‘Operations’

Use row operations to solve a system with two Equations

Use row operations to solve a system with two Equations

 

Row operations can be used to rewrite a matrix. The goal is a matrix in the form

\begin{bmatrix}  1 & a& \left.\begin{matrix}  &  & \\  &  &  \end{matrix}\right|b\\  0& 1 & \left.\begin{matrix}  &  & \\  &  &  \end{matrix}\right|c  \end{bmatrix}.

 

for systems with  equations, respectively. Notice that there are 1s down the diagonal from upper left to lower right and 0s below the 1s. A matrix written this way is said to be in row echelon form. When these matrices are rewritten as systems of equations, the value of one variable is known, and the rest can be found by substitution. The following examples illustrate this method.

Order of Operations

Order of Operations

a. Work separately above and below any fraction bar.

b. If grouping symbols such as parentheses ( ), square brackets [ ],

or absolute value bars \left |  \right | are present, start with the innermost set

and work outward.

c. Evaluate all powers, roots, and absolute values.

d. Do any multiplications or divisions in order, working from left to

e. Do any additions or subtractions in order, working from left to

 

  5 + 2 . 3 Multiply.

= 5 +  6 Add

= 11 .