2.3 subtracting integers addition problem
TRANSCRIPT
Math 078 Prealgebra 8th Edition Lesson Notes
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2.3 Subtracting Integers
2.3 Objective A: Subtract integers.
To subtract integers, we will write the subtraction problem as an addition problem.
Then we can use the two rules for addition from section 2.2.
Ex. 1. Subtract.
a. 13 – 4
b. -8 – 2
c. 11 – (-15)
d. -9 – (-1)
e. 6 – 9
f. -14 – 5
g. -3 – (-4)
2.3 Objective B: Add and Subtract integers.
Ex. 2 Simplify
a. −+ − < − - − (−.)=.0 + (−-) − ? − (−/)
Subtracting Two Numbers
If a and b are numbers, then ) − @ = ) + (−@)
AND
) − (−@) = ) + @
Math 078 Prealgebra 8th Edition Lesson Notes
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2.3 Objective C: Evaluate an Algebraic Expression by Subtracting.
Ex. 3 Evaluate 2: − ; for the given replacement values.
A) x = 4 and y = -4 B) x = 1 and y = -18
2.3 Objective D: Solve Problems by Subtracting integers.
Ex. 4. The highest point in Asia is the top of Mount Everest, at a height of 29,028 feet
above sea level. The lowest point is the Dead Sea, which is 1,312 feet below sea level.
How much higher is Mount Everest than the Dead Sea?
Group Review: pg. 120 #10, 18, 22, 40, 44, 46, 58, 60, 68
Math 078 Prealgebra 8th Edition Lesson Notes
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2.4 Multiplying and Dividing Integers
2.4 Objective A: Multiply Integers.
Ex. 1. Multiply
a. −3 ∙ 8
b. −6(−2)
c. −8(−3)(−3)
d. −6!
e. (−6)!
f. (−1)"
g. (−1)#
Multiplying Numbers
The product of two numbers
having the _____________ sign
is a positive number.
LIKE SIGNS:
(+)(+) = ________
(−)(−) = ________
The product of two numbers
having ______________ signs
is a negative number.
DIFFERENT SIGNS:
(−)(+) = ________
(+)(−) = _________
Math 078 Prealgebra 8th Edition Lesson Notes
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2.4 Objective B: Divide Integers.
Ex. 2. Find each quotient.
a. −24 ÷ 3
b. $%%$%
c. &$!'
d. $'"&
2.4 Objective C: Evaluate an Algebraic Expression by Multiplying or Dividing.
Ex. 3. Evaluate )@ and () for the given replacement values.
1) ) = −8and@ = 7 2) ) = −16and@ = −4
3) ) = 17and@ = 0
Dividing Numbers
The quotient of two numbers
having __________________ signs
is a negative number.
DIFFERENT SIGNS:
(+)
(−)= ______
(−)
(+)= _______
The quotient of two numbers
having the _______________
sign is a positive number.
LIKE SIGNS:
(+)
(+)=(−)
(−)= _______