1. Warm-up 1. 5x – 4 = 2x + 8 2. -4(x + 2) + 3x = 2
Solve for the variable
1. 5x – 4 = 2x (x + 2) + 3x = 2

2. Graph to find the solution.

3. *Homework Questions*

4. **Daily Check**

5. Coordinate Algebra with Support
UNIT QUESTION: How do I justify and solve the solution to a system of equations or inequalities?
Standard: MCC9-12.A.REI.1, 3, 5, 6, and 12
Today’s Question:
When is it better to use substitution than elimination for solving systems?
Standard: MCC9-12.A.REI.6

6. Solve Systems of Equations by Substitution

7. One equation will have either x or y by itself, or can be solved for x or y easily.
Substitute the expression from Step 1 into the other equation and solve for the other variable.
Substitute the value from Step 2 into the equation from Step 1 and solve.
Your solution is the ordered pair formed by x & y.
Check the solution in each of the original equations.
Substitution

8. Ex. 1
(-4, 16)

9. Ex. 2
(2, 1)

10. Ex. 3
(-2, -3)

11. Ex. 4
(8, 22)

12. Ex. 5
No Solution

13. Ex. 6
(12, -1)

14. Finish the back for HW