Final answer:
The addition property of equality involves adding the same number to both sides of an equation to isolate the variable, cancelling out the number that is combined with the variable.
Step-by-step explanation:
When using the addition property of equality, you would add whatever number is necessary to isolate the variable on one side of the equation. To do this, you should identify the number that is being subtracted from the variable. Your goal is to perform a balancing act, where you add the same number on both sides of the equation to cancel out the number opposite in sign to the variable. This process will leave the variable alone on one side of the equal sign.
For example, if you have an equation x - 4 = 10, you want to isolate x. You would add 4 to both sides to cancel out the -4, leading to x = 14. Here, you've successfully isolated the variable using the addition property of equality.
Remember, the LibreTexts principle that subtraction or addition of the same number on the two sides of an equation does not change the equality. So when we add 4 to both sides of the equation x - 4 = 10, we maintain the equality and isolate x.