G7 unit 2 negative number and real number pptx ]
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For 2 - 5, we“start at 2 and move 5 units to the left” We end up at-3,so 2-5=-3.
Similarly, for -3 -4 we “start at -3 and move 4 units to the left” We end up at-7,so -3-4= -7.
Homework:
•
P10-11 :
No.1-4
Unit2
lesson 2
•2.2 Addition and Subtraction involving Negative Numbers
Review:
• 1.Can you explain what is negative number and positive number? • 2.What are opposite numbers ? • 3.What poverty of opposite numbers? • 4. Can you represent a real number on a number line?
Review:
If a number more than 0 , the number are called positive number
0 is neither positive number nor negative number
Integers : such as ….,-4,-3,-2,-1 ,0,1,2,3,4….
Exercise:
Are your answers right?
Number line数轴:
Three elements of a number line : direction方向, unit length单位 长度, origin原点。
smaller numbers
Negative numbers
Hint
• If you don’t see a negative or positive sign in front of a number it is positive.
+9
Summary:
• 1. Do you have any question? • 2.what do you learn in this lesson?
A number line is useful for adding and subtracting directed numbers. .
1.Adding a positive
When we add a positive number to another, we start at the first number mentioned and then move to the right the amount added.
7
opposite
-7
Negative Numbers Are Used in our life: Measure Temperature
Negative Numbers Are Used in our life: Measure Under Sea Level 30 20 10 0 -10 -20 -30 -40
Activity:
• Do you know whIntegers – Integers are all the whole numbers and all of their opposites on the negative number line including zero.
2.Subtracting a positive
When we subtract a positive number from another, we start at the first number mentioned and move the required number of units to the left. So, subtraction is the opposite of addition.
origin
bigger numbers
Positive numbers
Number line:
Such as: -3 and 3, -2and 2, -1and 1 are opposite numbers each other .
Summary : a and –a are opposite numbers each other ,so a+(-a)= 0 If a+b=o then a and b are opposite numbers each other .
G7 Unit 2 Integers, Rational Numbers and Real Numbers
•Unit 2 lesson 1 Negative numbers
Key words
• Positive numbers 正数 • Negative numbers 负数 • Integers 整数 • Whole numbers 自然数（非负整数） • Number line 数轴 • Less than 小于 • More than 大于
Negative Numbers Are Used in our life
Show Debt
Let’s say your parents bought a car but had to get a loan from the bank for £ 5,000. When counting all their money they add in -£ 5.000 to show they still owe the bank.
For 5+3, we “start at 5 and go 3 units to the right” Weendupat8,so 5+3=8:
Similarly, for -5 + 2 we “start at -5 and go 2 units to the right” Weendupat¡ 3, so -5+2=-3.
Similarly, for -3 -4 we “start at -3 and move 4 units to the left” We end up at-7,so -3-4= -7.
Homework:
•
P10-11 :
No.1-4
Unit2
lesson 2
•2.2 Addition and Subtraction involving Negative Numbers
Review:
• 1.Can you explain what is negative number and positive number? • 2.What are opposite numbers ? • 3.What poverty of opposite numbers? • 4. Can you represent a real number on a number line?
Review:
If a number more than 0 , the number are called positive number
0 is neither positive number nor negative number
Integers : such as ….,-4,-3,-2,-1 ,0,1,2,3,4….
Exercise:
Are your answers right?
Number line数轴:
Three elements of a number line : direction方向, unit length单位 长度, origin原点。
smaller numbers
Negative numbers
Hint
• If you don’t see a negative or positive sign in front of a number it is positive.
+9
Summary:
• 1. Do you have any question? • 2.what do you learn in this lesson?
A number line is useful for adding and subtracting directed numbers. .
1.Adding a positive
When we add a positive number to another, we start at the first number mentioned and then move to the right the amount added.
7
opposite
-7
Negative Numbers Are Used in our life: Measure Temperature
Negative Numbers Are Used in our life: Measure Under Sea Level 30 20 10 0 -10 -20 -30 -40
Activity:
• Do you know whIntegers – Integers are all the whole numbers and all of their opposites on the negative number line including zero.
2.Subtracting a positive
When we subtract a positive number from another, we start at the first number mentioned and move the required number of units to the left. So, subtraction is the opposite of addition.
origin
bigger numbers
Positive numbers
Number line:
Such as: -3 and 3, -2and 2, -1and 1 are opposite numbers each other .
Summary : a and –a are opposite numbers each other ,so a+(-a)= 0 If a+b=o then a and b are opposite numbers each other .
G7 Unit 2 Integers, Rational Numbers and Real Numbers
•Unit 2 lesson 1 Negative numbers
Key words
• Positive numbers 正数 • Negative numbers 负数 • Integers 整数 • Whole numbers 自然数（非负整数） • Number line 数轴 • Less than 小于 • More than 大于
Negative Numbers Are Used in our life
Show Debt
Let’s say your parents bought a car but had to get a loan from the bank for £ 5,000. When counting all their money they add in -£ 5.000 to show they still owe the bank.
For 5+3, we “start at 5 and go 3 units to the right” Weendupat8,so 5+3=8:
Similarly, for -5 + 2 we “start at -5 and go 2 units to the right” Weendupat¡ 3, so -5+2=-3.