Explain how to add/subtract positive/negative numbers.

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Welcome! Today we'll explore how to add and subtract positive and negative numbers. Understanding these operations is fundamental to algebra and everyday math. Let's start by visualizing positive and negative numbers on a number line. Now let's learn the three main rules for addition. First, when adding two positive numbers, simply add them normally and the result is positive. Second, when adding two negative numbers, add their absolute values and keep the negative sign. Third, when adding a positive and negative number, subtract the smaller absolute value from the larger one, and use the sign of the number with the larger absolute value. For subtraction, we use the Keep Change Change method, also known as KCC. First, keep the first number unchanged. Second, change the subtraction sign to an addition sign. Third, change the sign of the second number. This converts any subtraction problem into an addition problem, which we can solve using our addition rules. Let's practice with two examples. First, negative eight plus five. Since we have different signs, we subtract the absolute values: eight minus five equals three. We use the sign of the larger absolute value, which is negative, so the answer is negative three. Second, negative six minus negative four. Using the KCC method, this becomes negative six plus four. Again, different signs, so we subtract: six minus four equals two, and we use the negative sign, giving us negative two. To summarize what we've learned: For addition, when signs are the same, add the values and keep the sign. When signs are different, subtract the smaller from the larger and use the sign of the larger. For subtraction, always use the Keep-Change-Change method to convert to addition. Practice with number line visualization helps understand these operations, and these fundamental rules apply to all real number calculations in algebra.