20 MENIT BAHAS TUNTAS BILANGAN BULAT KELAS 7

Introduction

This tutorial will cover the fundamental concepts of integers, specifically focusing on addition and subtraction of integers as taught in grade 7 mathematics. It serves as a refresher on previously learned material and provides practical examples to help solidify your understanding.

Step 1: Understanding the Basics of Integers

• Definition of Integers: Integers are whole numbers that can be positive, negative, or zero. They do not include fractions or decimals.
• Significance of Signs: The sign of an integer indicates its position on the number line. Positive numbers are to the right of zero, while negative numbers are to the left.

Step 2: Addition of Integers

• When adding integers, pay attention to their signs:
  • Same Sign: Add the absolute values and keep the sign.
    • Example:
      • -12 + (-15) = -27 (both numbers are negative)
      • 12 + 9 = 21 (both numbers are positive)
  • Different Signs: Subtract the smaller absolute value from the larger absolute value and keep the sign of the number with the larger absolute value.
    • Example:
      • 21 + (-8) = 21 - 8 = 13 (positive number is larger)

Step 3: Subtraction of Integers

• Subtraction can be transformed into addition:
  • Change the subtraction of a negative number into addition.
    • Example:
      • 21 - (-8) = 21 + 8 = 29 (subtracting a negative equals adding a positive)
  • If subtracting a positive number, change the operation to addition and adjust the sign of the number being subtracted.
    • Example:
      • -34 - (-13) = -34 + 13 = -21 (subtracting a negative equals adding a positive)

Step 4: Handling Complex Operations

• When dealing with operations involving multiple integers:
  • Follow the order of operations (PEMDAS/BODMAS).
  • Simplify by combining like terms systematically.
• Always ensure to change signs appropriately when necessary.

Practical Tips

• Keep a number line handy: It helps visualize the operations and the effects of adding or subtracting.
• Practice with different examples: The more you practice, the better you will understand the rules of integer operations.
• Check your work: After solving, revisit your calculations to avoid simple mistakes.

Conclusion

Understanding and correctly applying the rules of integer addition and subtraction is crucial for mastering more complex mathematical concepts. By practicing the examples provided and following the outlined steps, you will reinforce your understanding of integers. Next steps could include tackling word problems involving integers or moving on to other mathematical topics such as multiplication and division of integers.