9y + (-9y) = 0 what property is this?

The property demonstrated in this equation is the additive inverse property.

The additive inverse property states that for any number a, the sum of a number and its additive inverse is equal to zero. In this equation, 9y and -9y are additive inverses of each other, so when they are added together, the result is zero.

The property being demonstrated in this equation is called the "additive inverse property." This property states that for any number or variable, when you add it to its additive inverse (the opposite), the sum will always be zero.

To solve this equation and understand the property being used, we'll break it down step by step:

1. The given equation is 9y + (-9y) = 0.
2. Start by recognizing that (-9y) is the additive inverse of 9y, as it has the opposite sign.
3. According to the additive inverse property, when you add a number to its additive inverse, the sum equals zero. In this case, when you add 9y and (-9y), you get 0.
4. So, the equation simplifies to 0 = 0, which is a true statement.

Hence, the property being demonstrated here is the additive inverse property.

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