Halloween WarmUp

1
Halloween Warm-Up

• Paul has two dozen Halloween cookies. He will eat
  three cookies on Sunday. On every day that
  follows, he will eat a number of cookies that is
  one greater than the day before. On what day will
  he find that he doesnt have enough cookies to
  follow this procedure?

2
Answer

• Thursday
• Sun -3 Mon- 4 Tues- 5 Wed -6
• 18 cookies eaten
• 24 -18 6 cookies left over, but on Thursday he
  needs to eat 7 cookies to continue his pattern.

3
Solving Two- Step Equations

• Lesson 4-4

4
Rules to Remember

• When solving an equation, the goal is to get the
  variable by itself.
• Addition and Subtraction are inverse operations.
  (opposites)
• Multiplication and Division are inverse
  operations. (opposites)

5
Dont Forget

• The equation is like a balance scale. Whatever
  you do to one side of the equation must be done
  to the other side of the equation.

6
How to solve two-step equations

• Undo the operations in the reverse order of the
  order of operations.
• You are using the work back-words strategy
• In order of operations we do multiplication or
  division first, then addition and subtraction.
  When solving an equation we do the opposite!

7
Integer Rules to Remember

• Adding Integers
• Same sign add and keep the sign
• Different sign subtract and keep the sign of
  the larger number
• Subtracting Integers
• Keep, Change, Change
• Follow the rules for addition
• Multiplying and Dividing Integers
• Same Sign Positive Answer
• Different Sign Negative Answer

8
Lets Try One

• 3x 2 23
• - 2 -2
• 21
• 3x 21
• 3 3
• x 7

The problem contains addition and multiplication.
Which one do we undo 1st?
9
Another Example

• -2y 7 3
• 7 7
• 10
• -2y 10
• -2 -2
• y -5

The problem contains subtraction and
multiplication. Which one do we undo 1st?
10
Last Example

• -3c 9 3
• -9 -9
• -6
• -3c -6
• -3 -3
• c 2

The problem contains addition and multiplication.
Which one do we undo 1st?
11
Now its your turn

• 5x 4 19
• 2t 7 -1
• 6m 1 -23
• -4w 4 8
• -7y 3 -25
• 3t 13 2

• x 3
• t -4
• m -4
• w -3
• y 4
• t 5

12
Homework

• Complete Lesson 4-4 2-24 evens