Which describes the positions on a horizontal number line?
A. All points to the left of one are positive when one is negative.
B. All points to the right of one are positive when one is negative.
C. All points to the left of zero are negative.
D. All points to the right of zero are negative.
Answer (1)
The question asks which statement accurately describes positions on a horizontal number line.
Option 1 is false because if one is negative, all numbers to its left are also negative.
Option 2 is false because if one is negative, numbers to its right could be negative or positive.
Option 3 is true because all points to the left of zero are negative.
Option 4 is false because all points to the right of zero are positive.
Therefore, the correct answer is: A llp o in t s t o t h e l e f t o f zero a re n e g a t i v e .
Explanation
Understanding the Number Line Let's analyze the options based on the properties of a horizontal number line. Remember, on a number line, numbers increase from left to right, zero is the origin, numbers to the left of zero are negative, and numbers to the right of zero are positive.
Analyzing Option 1
Option 1: "All points to the left of one are positive when one is negative." If 'one' is negative, all numbers to its left are also negative. This statement is false because it claims these numbers are positive.
Analyzing Option 2
Option 2: "All points to the right of one are positive when one is negative." If 'one' is negative, numbers to its right could be negative (closer to zero) or positive (further to the right). This statement is false because it claims all numbers to the right are positive.
Analyzing Option 3
Option 3: "All points to the left of zero are negative." This statement aligns with the fundamental properties of a number line. Numbers to the left of zero are indeed negative.
Analyzing Option 4
Option 4: "All points to the right of zero are negative." This is incorrect. Numbers to the right of zero are positive.
Conclusion The correct answer is the statement that accurately describes the number line.
Examples
Understanding number lines is crucial in various real-life scenarios. For instance, when dealing with temperatures, values below zero (to the left of zero on the number line) represent freezing temperatures, while values above zero (to the right) represent warmer temperatures. Similarly, in financial contexts, negative numbers can represent debts or losses, while positive numbers represent assets or gains. Visualizing these concepts on a number line helps in making informed decisions and understanding the relative magnitude of different values.
