2-9 Problem Solving

1
2-9 Problem Solving

• Objective To explore problem situations, and to
  translate verbal sentences and problems into
  equations or formulas and vice versa.

2
Drill 30

• 1.
• 2.
• 3.
• 4.

3
Explore the problem

• Shane has 4 dimes more than quarters and 7 fewer
  nickels than dimes. If Shane has 28 coins total,
  how many nickels dimes and quarters does he have?

4
Problem Solving Plan (24.)

• Explore the problem
• What is the problem asking
• What information are you given
• Plan the solution
• Define variables
• Set up equations
• Solve the problem
• Examine the Solution
• Does the answer makes sense?
• Check your answer

5
Explore the problem

• Strategies for working out problems
• Draw a diagram
• Make a table
• Guess and check
• Look for a pattern
• Work backwards
• Solve a simpler problem

6
Example 1 pg 127
7
Defining the Variable (25.)

• Definition choosing a variable to represent one
  of the unspecified numbers in the problem.
• Example
• Sam is ten years older than Mary.
• Sam s
• Mary m
• m 10 s

8
Words that indicate equality

• Is
• Equals
• Is equal to
• Is the same as
• Is as much as
• Is identical

9
Formula(26.)

• Definition an equation that states a rule or
  relationship between certain quanities.
• NOTE
• Examples
• A ½ bh V l(w)(h)
• d rt P 2l 2w

10
Exercise 9,13 pg 130
11
Write a problem

• b Brittanys height
• b 5 Tatianas height
• 2b (b 5) 194
• Write a problem based on this information.

12
Write an expression to represent the area of the
shaded region
b

• 5. 6.

a
3
c
t
2
s
d
13
Write an equation that represents the situation
below if the two lines are the same length.

• 7.

30
x
x
8
x