Download 7th Grade Math Mr. Trisler August 5, 2008

Warm-up
August 15, 2016
Solve the following:
1. 3/5 + 2/5 =
2. 1/3 + 2/3 =
3. 3/5 + 3/6 =
4. 2/3 + 3/5 =
5. 5/6 + 5/6 =
Vocabulary
1. Absolute Value: The distance between a
number and zero on the number line. The
symbol for AV is shown in the equation:
│ -8 │ = 8
2. Integers: The set of whole numbers and
their opposites (… -2, -1, 0, 1, 2, …)
3. Opposite numbers: Two different numbers
that have the same absolute value.
Example: 4 and -4 are opposites
More vocabulary
1. Positive Integer: an integer that is greater
than zero
2. Negative Integer: an integer that is less than
zero
3. Rational Number: the set of numbers that
can be written in the form A/B, where A and
B are integers and b is not equal to zero
Absolute value
• The distance from a number to zero on a
number line.
• Absolute values are ALWAYS positive.
Addition
SAME SIGNS (both signs are positive or both signs are
negative):
• Add the numbers and keep the sign – 2 positives stay
positive, 2 negatives stay negative
DIFFERENT SIGNS (one positive and one negative):
• Subtract the small number from the larger number
• Keep the sign of the larger number – if positive
number is larger, answer is positive; if negative
number is larger, answer is negative (absolute value)
Addition Song
•
•
•
•
Same sign add and keep
Different sign, subtract
Keep the sign of the larger number
Then you’ll be exact
(To the tune of Row, Row, Row, your boat)
Addition on a Number Line
• Always start at ZERO
• Draw your arrow from 0 to the first number in
the equation.
• Always start your second number where the
arrow for the first number ends.
• Draw the second arrow the length of the
absolute value of the number.
Subtraction
• Keep Change Change (KCC)
• Keep the sign of the first number – keep it as it is
• Change the problem from subtraction to addition ( sign becomes + sign)
• Change the sign of the second number – positive
number becomes negative, negative number
becomes positive
• Use the rules of addition (you changed it to an
addition problem!)
Subtraction on a Number Line
How?
Class work
Common Core Workbook
• Page 4
• Problems 1 through 10
• REMEMBER – YOU WILL BE DRAWING AND
USING A NUMBER LINE TO SOLVE EACH
PROBLEM (10 number lines!)