2.1 Adding Rational Numbers
vocab
additive inverse the opposite of a number
for example: the additive inverse of 3 is -3
the additive inverse of -17 is 17
Identity Property of Addition the sum of any real number and zero is equal to the original number,
for every real number n, n + 0 = n
Inverse Property of Addition the sum of any real number and its oposite is equal to zero,
for every real number n, there is an additive inverse such that
n + (-n) = 0
Using a number line:
You try:
2 + -7
7 + -5
-5 + 8
4 + -6
• Model the expression
• Make Zero pairs
• Remove zeros
Adding Integers
-3 + 2
A rock climber climbs a mountain, whose
base is 132 ft. below sea level.
Write an equation to help you find the climber's
height above or below sea level.
step 1: Relate:
step 2: Define:
step 3: Write:
Suppose our guy climbs 458 ft. What is his height relative to sea level?
(Use the equation you wrote to evaluate the situation.)
matrix a rectangular arrangement of numbers in rows and columns
element each value in a matrix
this is called a 3 x 2 matrix
3 columns
2 rows
Only matrices of the same size may be added!
To add matrices; add the corresponding elements.
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