The document discusses reviewing Khan Academy topics on systems of equations and solving 3x3 systems. It includes examples of solving systems of equations by elimination, addition, and substitution. Students will review methods, complete assignments, and take a five question quiz on solving systems of equations.

1.  Review Last Khan Academy Topic
Today
 Review Three Methods of Solving
 Solving 3 x 3 Systems of Equations
 CW 4.1-4.2 at or near Completion
 Grades will be completed Today
 Five Question Quiz

2. 9-1

3. 6 -7

5. Which of the following is a possible first step when
solving this system of equations by elimination?
5x + 2y = -1
x + 3y = -8
A) Multiply the first equation by -1
B) Multiply the second equation by -1
C) Multiply the first equation by -5
D) Multiply the second equation by -5

6. If you want to solve this system of equations by adding,
which of the following represent the correct steps?

7. Applying Systems of Equations:
Mrs. Smith took her family and friends to the movies.
There were a total of 12 people. Children tickets cost $5 and
adult tickets cost $10. She spent a total of $95. How many
adults & how many children went to the movies?

8. 1. Mark
the text.
2. Label
variables.
3. Create
equations.
4. Solve.
5. Check.
A restaurant charged one customer $28.20 for
3 small dishes and 5 large dishes and charged
another customer $23.30 for 4 small dishes
and 3 large dishes. What will 2 small and 4
large dishes cost?

9. Solving 3x3 Systems:(1)
The graph of the solution set of an equation in three
variables is a plane, not a line. In fact, graphing equations in
three variables requires the use of a three-dimensional
coordinate system. It is therefore, not practical to solve
3x3 systems by graphing
Solve the System: 4x + 2y - z = -5
3y + z = -1
2z = 10
1. Which is the easiest
variable to solve for?
2. Plug in where and solve
for what?
3. Substitute y and z values into equation 1; solve for x.
4. Substitute all values, check for equality.
5. The solution set is (1, -2, 5)
Solving 3x3 Systems: