Section 1
📘 Number Lines
New Concept
Numbers less than zero are called negative numbers.
What’s next
Next, you’ll use the number line as a tool to visualize these new numbers and compare their values.
In this Grade 4 lesson from Saxon Math Intermediate 4, students learn to draw and interpret number lines by placing equally spaced tick marks and labeling them using skip-counting intervals such as twos, fives, and tens. Students are introduced to positive and negative numbers, including how negative numbers represent values like temperatures below zero and debt. The lesson also covers using greater than and less than symbols to compare two numbers based on their positions on a number line.
Section 1
📘 Number Lines
Numbers less than zero are called negative numbers.
Next, you’ll use the number line as a tool to visualize these new numbers and compare their values.
Section 2
Number line
A number line is a line with equally spaced tick marks labeled with numbers. The labels show the distance from zero. The space between tick marks, or the scale, can be ones, twos, fives, or any other number. This helps us visualize where numbers are located in relation to one another on an infinite line.
To what number is the arrow pointing on a line from 0 to 20 with tick marks at every multiple of 2, and the arrow on 14?
The arrow points to 14.
To what number is the arrow pointing on a line from 0 to 100 with tick marks at every multiple of 10, and the arrow on 70?
The arrow points to 70.
Think of a number line as a giant, endless ruler! It’s a map that shows exactly where every number lives, helping you see the distance and order between them easily. Just figure out the distance between tick marks, and you can find any number.
Section 3
Negative numbers
Numbers less than zero are negative numbers, written with a minus sign to the left of the digit, like . Zero itself is neutral—neither positive nor negative. Negative numbers are super useful for describing things like very cold temperatures below zero, or when you owe someone money, which is also known as a debt.
Use digits to write negative twenty: .
If the temperature starts at 6 degrees and drops 10 degrees, what is the new temperature? The new temperature is degrees.
If you have 5 dollars but owe someone 8 dollars, your financial situation can be represented as dollars.
Negative numbers are the mirror image of positive numbers on the other side of zero. They represent opposites, like owing three dollars () instead of having three dollars (), or a temperature drop!
Section 4
Comparing numbers
To compare two numbers, we decide if one is greater than (), equal to (), or less than () the other. On a number line, numbers get greater as you move to the right and smaller as you move to the left. The comparison symbol always points to the smaller number, like a hungry alligator wanting the bigger meal!
Compare and . Since is to the right of on a number line, .
Compare and . Since is to the right of on a number line, .
Arrange from least to greatest: . The correct order is .
Comparing numbers is like figuring out who is further ahead in a race. The number further to the right on the number line is always the winner, or the greater number, no matter if it's positive or negative!
Book overview
Jump across lessons in the current chapter without opening the full course modal.
Continue this chapter
Expand to review the lesson summary and core properties.
Section 1
📘 Number Lines
Numbers less than zero are called negative numbers.
Next, you’ll use the number line as a tool to visualize these new numbers and compare their values.
Section 2
Number line
A number line is a line with equally spaced tick marks labeled with numbers. The labels show the distance from zero. The space between tick marks, or the scale, can be ones, twos, fives, or any other number. This helps us visualize where numbers are located in relation to one another on an infinite line.
To what number is the arrow pointing on a line from 0 to 20 with tick marks at every multiple of 2, and the arrow on 14?
The arrow points to 14.
To what number is the arrow pointing on a line from 0 to 100 with tick marks at every multiple of 10, and the arrow on 70?
The arrow points to 70.
Think of a number line as a giant, endless ruler! It’s a map that shows exactly where every number lives, helping you see the distance and order between them easily. Just figure out the distance between tick marks, and you can find any number.
Section 3
Negative numbers
Numbers less than zero are negative numbers, written with a minus sign to the left of the digit, like . Zero itself is neutral—neither positive nor negative. Negative numbers are super useful for describing things like very cold temperatures below zero, or when you owe someone money, which is also known as a debt.
Use digits to write negative twenty: .
If the temperature starts at 6 degrees and drops 10 degrees, what is the new temperature? The new temperature is degrees.
If you have 5 dollars but owe someone 8 dollars, your financial situation can be represented as dollars.
Negative numbers are the mirror image of positive numbers on the other side of zero. They represent opposites, like owing three dollars () instead of having three dollars (), or a temperature drop!
Section 4
Comparing numbers
To compare two numbers, we decide if one is greater than (), equal to (), or less than () the other. On a number line, numbers get greater as you move to the right and smaller as you move to the left. The comparison symbol always points to the smaller number, like a hungry alligator wanting the bigger meal!
Compare and . Since is to the right of on a number line, .
Compare and . Since is to the right of on a number line, .
Arrange from least to greatest: . The correct order is .
Comparing numbers is like figuring out who is further ahead in a race. The number further to the right on the number line is always the winner, or the greater number, no matter if it's positive or negative!
Book overview
Jump across lessons in the current chapter without opening the full course modal.
Continue this chapter