The document contains examples and explanations of solving systems of equations and inequalities, including: 1) An example of solving a 3x3 system of equations by substitution. 2) An word problem involving a system of equations about restaurant dishes and their costs. 3) Instructions for graphing and solving a system of two inequalities, including rewriting the inequalities in slope-intercept form and shading the overlapping region that represents the solution.

1. Today:

3. Write the system of inequalities that produced this graph.Is it: -6x – 2y > -4, y > -1

4. Solving 3x3 Systems (1)
x + y + z = 3
2x – y + 4z = 5
x + 4y – 2z = 3
x + y + z = 3
2x – y + 4z = 5
2x – y + 4z = 5
x + 4y – 2z = 3
Applying Systems of Equations (2)
A restaurant charged one customer $25.00 for 3 small dishes
and 5 large dishes and charged another customer $20.50 for
4 small dishes and 3 large dishes. What will 2 small and 4
large dishes cost?
4( )
3x + 5z = 8 9x + 14z = 23
9x + 14z = 23
-3( )
-z = -1( __, __, 1 )

5. Solving Systems of Inequalities (1)
Practice 1. Find the solution to:
x + y < 1; x - y > 1
1: Rewrite in slope-intercept form:
x - y > 1;
2: Graph the first line.
3: Lightly shade the correct side
of the line.
4: Repeat steps 2 & 3 for the 2nd
line.
5: Heavily shade the
overlapping areas, which is the
solution.
x + y < 1;
y < x - 1
y < -x + 1

6. Parallel & Perpendicular Lines (1)

7. Inequalities:
Which graph represents the inequality 6y – 8x < -24

8. Complete Class Work 3.4:
 Ask Questions if unsure,