Adding and Subtracting Mixed Numbers with Negatives and Parentheses

🔑 Key Concepts

• A negative outside parentheses means multiply by −1.
• Two consecutive negatives make a positive.
• Subtracting a negative is the same as adding.
• Always determine the sign before performing fraction operations.
• Find common denominators when adding or subtracting mixed numbers.

✏️ Worked Examples – Add & Subtract Positive and Negative Mixed Numbers

🧠 Math Vocabulary

• Parentheses: Symbols used to group numbers together.
• Absolute Value: The distance a number is from zero.
• Common Denominator: The same denominator used when adding or subtracting fractions.
• Opposite: A number with the same distance from zero but a different sign.
• Difference: The result of subtraction.

💡 Main Idea

When a negative appears outside parentheses, think of it as multiplying by −1. This changes the sign of the number inside the parentheses. Two negatives make a positive. Always determine the sign first, then perform the fraction operation by finding common denominators and combining values.

📚 What You Should Already Know

You should know how to add and subtract mixed numbers, find common denominators, and understand how positive and negative numbers behave on a number line.

🚀 What Comes Next

Next, students will apply these same rules when evaluating multi-step expressions involving fractions and negative numbers using the order of operations.