process versus the reason why 1.because subtraction means to take away 2.because multiplication and...

Process versus The Reason Why

1. Because Subtraction Means to Take Away

2. Because Multiplication and Division of Integers Follow a Pattern

3. Because it Makes Sense

Because Subtraction Means to

Take Away

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What is 5 – (-6) ?+

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The Answer is 11.

What is 3 - 6 ?+

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The Answer is -3.

Because Multiplication and Division

of Integers F

ollow a Pattern

Why does a positive times a negative equal a negative?

4 • 3 = 124 • 2 = 8 4 • 1 = 44 • 0 = 0

4 • -1 = ?Look at th

e patternThe Answer is -4.

So a positive times a negative is a negative.

But why does a negative times a negative equal a positive?

-4 • 3 = -12-4 • 2 = -8 -4 • 1 = -4-4 • 0 = 0

-4 • -1 = ?

Look at the pattern

The Answer is 4.

So a negative times a negative is a positive.

Well, knowing a positive times a negative is a negative, also means that a negative times a positive is a negative, so again…

Because It Makes Sense

Floors on Elevators

This is an elevator panel with NEGATIVE numbers.

How far many floors have you gone up if you start at the lowest floor and go to the highest floor?

(1)Set up the expression(2)Explain your reasoning(3)Solve the problem

Answer: 17-(-2) = 19 floors

The World’s Tallest Building

http://img.dailymail.co.uk/i/pix/2007/07_02/WorldsTallestDM_468x525.jpg

How much taller is The Burj Dubai compared to The Empire State Building?

Answer: 512 – 381 = 131 meters

The U.S. National Debt

U.S. NATIONAL DEBT CLOCK The Outstanding Public Debt as of 09 Jan 2010 at 01:30:59 PM GMT

is:

http://www.brillig.com/debt_clock/

If the government taxed each American $40, 068.00, approximately how many Americans would it require to pay to off our National Debt?

Answer: -12,287,322,881,897 ÷ -40,068.00 ≈ 306,666,778 Americans

Why Do I Need to Know This?(Motivation and Real World Applications)

http://www.labsafety.com/images/xl/Weather-Thermometer-40-to-LSS_i_LBM37561Z.jpg

What is the difference between the lowest and the highest temperature reading on the thermometer?

Answer: 120 – (-40) = 160°F

Above and Below Sea Level

http://www.treehugger.com/mariana%20trench.jpg

http://www.thetravelpeach.com/asia-vacations/everest-mount.jpg

Mariana Trent-10,916

Mount Everest29,035

What is the difference between the highest point above sea level and the lowest point below sea level?

Answer: 29,035 – (-10,916) = 39,951