Integers

Summary and Exam Tips for Integers

Integers is a subtopic of Numbers, which falls under the subject Mathematics in the IB MYP curriculum. An integer is a whole number that can be positive, negative, or zero. A fundamental property of integers is that the sum of any integer and its opposite equals zero. For example, $+4 + (-4) = 0$. When adding integers, adding a positive number is straightforward addition, while subtracting a negative number is equivalent to adding. Conversely, subtracting a positive number or adding a negative number results in subtraction.

Key rules include:

• Two like signs become a positive sign: $3 + (+2) = 5$.
• Two unlike signs become a negative sign: $7 + (-2) = 5$.

When starting with a negative number, using a number line can be helpful. For instance, $-3 + (+2)$ involves moving forward on the number line, resulting in $-1$. Conversely, $-3 + (-2)$ involves moving backward, resulting in $-5$.

Exam Tips

• Understand the Sign Rules: Remember that two like signs become positive, and two unlike signs become negative. This is crucial for solving integer problems correctly.
• Use a Number Line: Visualizing problems on a number line can simplify understanding of how positive and negative integers interact.
• Practice Basic Operations: Regularly practice adding and subtracting integers to build confidence and speed.
• Check Your Work: Always double-check your calculations, especially when dealing with negative numbers, to avoid simple mistakes.
• Apply Real-Life Scenarios: Relate integer operations to real-life situations, such as bank transactions, to better grasp the concepts.