1. Lesson 89.Day1.notebook April 28, 2014
Assignment:
1-->System of equations Handout - Due Tomorrow [4/29]

2. Lesson 89.Day1.notebook April 28, 2014
Lesson 89 WarmUp:
1) If value of a $100 stock drops 10% one year, then increases 10% the
next year, what is the value of the stock at that time?
2) Simplify: 2 6 15
3) Solve: x - 4 = 3x + 2
Graph the following by finding the x-intercept & y-intercept:
4) x + y = 3
5) 3x - 2y = 12

3. Lesson 89.Day1.notebook April 28, 2014
Lesson 89
*Mr. Lochmann is thinking of 2 numbers...
**The sum of the 2 numbers is 6...
***And one number is 10 more than the other number...
WHAT ARE THE 2 NUMBERS?
--We could use "guess and check", but there are several other
ways!

4. Lesson 89.Day1.notebook April 28, 2014
One way is to write the information as two equations
**The sum of the 2 numbers is 6...
Could be written as:
**And one number is 10 more than the other number...
Could be written as:
If we use the same variables and put these 2 equations together
they form a SYSTEM OF EQUATIONS. To solve them, we must
find a value [ordered pair] that works in both of them.

5. Lesson 89.Day1.notebook April 28, 2014
**This lesson we will do it by "Graphing"!
EX--> x + y = 6
y = x + 10
X
y

6. Lesson 89.Day1.notebook April 28, 2014
Examples - Lesson 89
Solve each problem by graphing the system of equations and checking
the solution.
A) Together Julie and Emily have $12. Emily has $6 more than Julie.
How much money does each of them have?
X
y

7. Lesson 89.Day1.notebook April 28, 2014
B) Josh is thinking of 2 numbers. Their sum is 12. The greater number
is twice the smaller number. What are the 2 numbers?
X
y

8. Lesson 89.Day1.notebook April 28, 2014
C) Use graphing to solve this system of equations:
x + y = 6
y = x
X
y

9. Lesson 89.Day1.notebook April 28, 2014
D) Use graphing to solve this system of equations:
y = x - 6
x + y = 0
X
y

10. Lesson 89.Day1.notebook April 28, 2014
X
y
E) Use graphing to solve this system of equations:
y = -x + 1
y = x + 5