Transcript Most Common Errors on the Quiz Sections 2.1-2.3

Most Common Errors
on the Quiz Sections 2.1-2.3
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Real Number Order
Absolute Value
Adding Real Numbers
Word Problems
Time to review strategies and learn
where we can improve!
Write in descending order
Don’t forget to put into decimal
form FIRST before you write!
5 2
1 4
7,  , , 0,  ,
6 3
2 5
Reading a Table
• The table below shows the temperatures in
Canada for five consecutive days. List the days
the temperature was above 5˚F.
Time
Day 1
Temp. 2˚ F
Day 2
Day 3
Day 4
Day 5
-6 ˚F
6 ˚F
-5 ˚F
7 ˚F
Compare Two Quantities
• When asked to compare quantities, think
of comparing a very tall person to a very
short person and the reverse!
• Compare -5 and -3. Don’t forget you can
use TWO different inequality signs!
Evaluating Absolute Value
• When evaluating
absolute value, find
the absolute value
first THEN worry
about any opposite
signs outside the
absolute value signs!
Evaluate 2  3
Evaluate  5
Evaluate  5  6
Evaluating for x in absolute value
• Find the solution for
each of the following:
x 5
x 0
x  7
DON’T FORGET!
When finding the value for x in
an absolute value situation:
If the value is positive you will
have ____ solutions.
If the value is zero you will have
____ solutions.
If the value is negative you will
have ____ solutions
What property am I?
• 5+6=6+5
• 5 + (6 + 7) = ( 5 + 6) + 7
• 4 + (-4) = 0
• 4+0=4
• 4(2 + 3) = 4(2) + 4(3)
Counter Examples
• When a statement is false, the counter
example is the ONE statement that can
prove it is false!
• Example: Your math teacher is a man!
• Counter Example: Mrs. Rose is a woman
• Now you try!
• 2+3=6
Word Problems
• A balloon is rises 473 feet. It then
descends 120 feet. Assuming it started at
sea level, where is the balloon now?
What does – mean again?
• 12 + 4 – (2-3)
• The negative sign in front of the
parenthesis MUST be distributed!!!!
• Rewrite the problem to read
• 12 + 4 – 2 + 3
• Then solve!
Adding Real Numbers
• THINK MONEY
• It is either in your pocket OR you owe it!
• -6 + -6 MEANS you owe 6 and then you owe 6
more! Did you have any money or did you
always owe?
• 2 + (-9) MEANS you had 2 but you OWE me 9.
Can you pay me all you owe?
• -5 + 7 MEANS you had 7, you owe me 5. Can
you pay me? Do you have anything left?
Now you try!
• 6 + (-10) + 6
• 7 + (-2) + (-9)
• -8 + 4 + (-4)
• 4 + ½ - 1/3
• 1/7 + (-2) + (-5/7)
Individual practice
• Pages 121-122 #1 -17
• Homework tonight in TWO parts
• Part 1: Correct all incorrect problems on
quiz
• Part 2: Page 83 Quiz #1