Transcript Chapter 1 Section 1-2

Chapter 1
Section 1-2
Exponents and Order of Operations
Problem of the Day
• Which equation models the
relationship in the table if
“r” represents the row
number and “t” represents
the number of tulips?
A. r= 3t
B. r = 3
t
C. t = r + 3
D. t = 3r
Row Number
Number of Tulips
1
3
2
6
3
9
4
12
Problem of the Day
Answer is D. t = 3r
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T= total # of tulips
R = total # of rows
1 row of tulips = 3 tulips
2 rows of tulips = 6 tulips
3 rows of tulips= 9 tulips
Do you see the pattern?
Lets Get Started
Vocabulary
• Simplify= replace a numerical expression with its
simplest name. AKA= Solving a multiple step
problem
• Exponent= tells how many times a number
• Base= it’s a factor
• Power= has two parts, a base and an exponent
Order of Operations
• To solve math problems with more than one
operation (+, -, x, ÷ ), remember this order
• Please Excuse My Dear Aunt Sally
• Please = Parentheses
• Excuse= Exponents
• My Dear= Multiply and/ or Divide
• Aunt Sally= Add and/ or Subtract
2
Simplify 25 – 8 x 2 + 3
• There are no parentheses, so I simplify the power
• Next, I multiply 8 x 2
• Then, I subtract
• Now I solve:
3
Evaluate 3a – 2 ÷ b
for a = 7 and b = 4
• I substitute 7 for a, and 4 for b
• Simplify the power
• Multiply and Divide from left to right
• Subtract
The equation c= p + 0.06p represents the cost “c” of a pair of
sneakers with price “p” and sales tax of 6%. Use a table to
find the cost for $45, and $59 pairs of sneakers.
Price
P
P + 0.06p
Cost
C
$20
20 + 0.06(20)
$21.20
$30
30 + 0.06(30)
$31.80
$45
45 + 0.06(45)
$59
59 + 0.06(59)
Simplify 15( 13 – 7) ÷ ( 8 – 5)
• Simplify with Parentheses first
• Multiply and Divide from left to right
Evaluate each expression for c= 15 and d= 12
2
2
(cd)
cd
2
• (15 x 12)
Substitute
2
• (180)
Simplify
within parentheses
• 32,400
2
• 15 x12
• 15 x 144
power
• 2,160
Substitute
Simplify the
Simplify
2
Simplify 2[(13 – 7) ÷ 3]
• First, simplify within the parentheses
• Simplify the exponent
• Divide within the bracket
• Multiply
A neighborhood association turned a vacant lot into a park.
The park is shaped like the trapezoid below.
A = h (b1 + b2)
2
Substitute 130 (100 + 200)
2
Simplify
130 (300)
the numerator
2
Image 1
B1= 100 ft
H= 130ft
Simplify the fraction 130(150)
Multiply
= 19,500
b2= 200 ft
Lets Check Your Understanding
Problem 1
•
3
Simplify 5 - 15 ÷ 2 + 2
Problem 2
• Evaluate
2ab + c
For a= 3.3 b= 4.5 c= 2
Answers!!!
Problem 1
• Answer is 119.5
Problem 2
• Answer is 31.7
Homework Time!
• In your text book, complete pages 12-13,
numbers 2-30 even