Identities and Properties - Pre-Algebra

The thousands place will always be the forth digit to the left of the decimal point.

The thousandths place will alway be the third digit to the right of the decimal.

The tens place will always be the second digit to the left of the decimal point.

The tenths place will always be the first digit to the right of the decimal point.

The hundreths place will always be the second digit to the right of the decimal point.

The thousandths place will always be the third digit to the right of the decimal point.

The thousands place will always be the forth digit to the left of the decimal point.

The tenths place is always the first digit to the right of the decimal point.

By the additive identity property, zero added to a number yields that second number as the sum. This is shown by the statement

.

Pre-algebra brings with it many different properties for memorization, and it is easy to forget one or mix two of them up. But maybe we can jog our memory by looking closely at the name of the property. The first word in the additive identity property is "additive". This tells us very quickly that the property involves addition. That means we can already eliminate any answer choices that don't involve adding, which in our case is the choice .

With four choices left, we look at the next word in the name, "identity". The identity of something is what the thing is. In order for a spy to avoid being caught, he/she might change their idenity. They might take a different name, wear a wig, fake an accent, or dress differently. If the value of a number changes, its identity changes. In math, the only number I can add to any number without changing its value is 0. Therefore, we call 0 the additive identity because adding it preserves the identity of a number. This fact--namely that adding 0 to a number results in the same number--is what we call the Additive Identity Property.

If we look once more at our answer choices, the only one involving the addition of 0 to a number is the choice . This is the correct answer.

The additive inverse property is when two numbers added together equal zero. So,

displays that property.

The associative property of addition states:

When considering only addition and subtraction, the order of operations does not matter.

When something is multiplied by the number one it remains the same number. Therefore when multiplying by one it creates its own identity.

Multiplicative Identity Property

The identity property of addition states that there is a number 0, called the additive identity, that can be added to any number to yield that number as the sum. Of the four statements,

demonstrates this property.

The additive identity property states that adding zero to any value will leave the value unchanged. The equations that will best describe this scenario is:

Zero is the additive identity.

The above two equations are the only possible correct answers.

The inverse property of addition states that for every real number, a number exists, called the additive inverse, such that the number and its inverse have sum 0. Of the statements given, only

demonstrates this property, so it is the correct choice.

The additive inverse of is . This means that when is added to the result is zero.

can be written as .

Since zero is the only number that is neither positive nor negative the answer is .

The rule for Additive Inverse Property is .

Using this rule if ,

So the additive inverse is .

The question asks us what number added with 30 will equal zero. Write the mathematical equation that represents this scenario.

Subtract 30 from both sides.