Adding and Subtracting Integers and Absolute Value

subtracting integers (rule)

• subtract their absolute value; keep the sign of the integer with the higher absolute value

• add their absolute value and keep the sign of the integers

• change subtraction sign (between the integers) to an addition sign and change the sign of the integer following it to its opposite (if it was positive, make it negative; if it was negative, make it positive); then solve

adding integers with DIFFERENT signs

• subtract their absolute value; keep the sign of the integer with the higher absolute value

• add their absolute value and keep the sign of the integers

• change subtraction sign (between the integers) to an addition sign and change the sign of the integer following it to its opposite (if it was positive, make it negative; if it was negative, make it positive); then solve

adding integers with the SAME sign

• add their absolute value and keep the sign of the integers

• subtract their absolute value; keep the sign of the integer with the higher absolute value

• change subtraction sign (between the integers) to an addition sign and change the sign of the integer following it to its opposite (if it was positive, make it negative; if it was negative, make it positive); then solve

Define Absolute Value

• The distance a number is from zero

• The highest number in the number line

• The opposite of the value

Solve by using the number line:

-9 + (-5) = ?

• -14

• 4

• 14

• -4

Solve by using the number line:

10 + (-4) = ?

• -6

• 14

• 6

• -14

Solve by using the number line:

-2 + 4 = ?

• -2

• 0

• 2

• 4

Which is the definition of an Additive Inverse?

• The sum of two numbers.

• The distance away from 0.

• Two numbers with the sum of zero.

What is the definition of Absolute Value?

• Two numbers with the sum of 0.

• The distance away from 0.

• Whether a number is negative or positive.

Which one is an Additive Inverse?

• -10 + -10

• 8 - 4

• -4 - (-4)

• 4 + (-4)