Chapter 1

Unit Question

How do numbers measures, graphical representations and expressions represent

mathematical situations?

Open Learning Logs

Date on Left…Section 1 – 4 on right

WARM UP 1 – 4

Identify the which quantity in each of the following situations must come first...

1. As the temperature increases, the more Mr.

Hoffman sweats.

2. Joanie earns more money the longer she

works.

3. The more homework Freddie has, the less time

he has for T.V.

Section 4

How do we use variables to describe patterns?

Homework Check

To cube a number means…

To multiply that number by itself 3 times

What are two instances (examples) of this situation?

13 = 1 • 1 • 1 33 = 3 • 3 • 3

What would this pattern look like using a variable…say…x ?

x3 = x • x • x

43,560

An acre is a measurement of land areathat equals 43,560 square feet…

If I have 1 acre of land, how many square feet is that?

How would I calculate the square feet for 2 acres?…3 acres?

# acres Square feet

123

1 • 43,5602 • 43,5603 • 43,560

To write the square feet pattern using a variable, ask yourself, “What is NOT changing?”

•x

There is the key to today’s lesson…line ‘em up, ask the question.

If it is not changing, keep it…If it does, use a variable!

Try this…Line ‘em up!

7(6 – 1) = 7 • 6 – 7 • 1

7(5 – 2) = 7 • 5 – 7 • 2

7(4 – 3) = 7 • 4 – 7 • 3

Ask the question...keep it or use a variable!

7(x – y) = 7 • x – 7 • y

In Joe’s Deli, a Salad costs $1.75 and a Juice costs $1.25

Write a pattern to calculate the Total cost

of S salads and J juices

How much for a meal of one salad and one juice?

1 • $1.75 + 1 • $1.25 = $3.00

You invite 2 friends to go with you. How much for all three meals?

3 • $1.75 + 3 • $1.25 = $9.00

S • $1.75 + J • $1.25 = T

Counterexamples!!!…(prove me wrong)

a • b > a + bFind values for a and b that make this statement false!

If I let…a = 0b = 1Then we have…

a • b > a + b

0 • 1 > 0 + 1

0 > 1

Which is NOT true, therefore we have proven the original statement

false!

Homework

• Do HoffmaSheet 1 – 4