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1)1) Evaluate the expression:Evaluate the expression:
a) l5la) l5l b) l-13lb) l-13l c) – l0.56lc) – l0.56l
2)2) Use mental math to solve the equation:Use mental math to solve the equation:
a) lxl = -10a) lxl = -10 b) lxl = 2.7b) lxl = 2.7
3)3) Find the sum:Find the sum:
a) -6 + (-7)a) -6 + (-7) b) 4 + (-10)b) 4 + (-10)
4
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1)1) Evaluate the expression:Evaluate the expression:
a) l5la) l5l b) l-13lb) l-13l c) – l0.56lc) – l0.56l
2)2) Use mental math to solve the equation:Use mental math to solve the equation:
a) lxl = -10a) lxl = -10 b) lxl = 2.7b) lxl = 2.7
3)3) Find the sum:Find the sum:
a) -6 + (-7)a) -6 + (-7) b) 4 + (-10)b) 4 + (-10)
3
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1)1) Evaluate the expression:Evaluate the expression:
a) l5la) l5l b) l-13lb) l-13l c) – l0.56lc) – l0.56l
2)2) Use mental math to solve the equation:Use mental math to solve the equation:
a) lxl = -10a) lxl = -10 b) lxl = 2.7b) lxl = 2.7
3)3) Find the sum:Find the sum:
a) -6 + (-7)a) -6 + (-7) b) 4 + (-10)b) 4 + (-10)
2
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1)1) Evaluate the expression:Evaluate the expression:
a) l5la) l5l b) l-13lb) l-13l c) – l0.56lc) – l0.56l
2)2) Use mental math to solve the equation:Use mental math to solve the equation:
a) lxl = -10a) lxl = -10 b) lxl = 2.7b) lxl = 2.7
3)3) Find the sum:Find the sum:
a) -6 + (-7)a) -6 + (-7) b) 4 + (-10)b) 4 + (-10)
1
1)1) Evaluate the expression:Evaluate the expression:
a) l5la) l5l b) l-13lb) l-13l c) – l0.56lc) – l0.56l
2)2) Use mental math to solve the equation:Use mental math to solve the equation:
a) lxl = -10a) lxl = -10 b) lxl = 2.7b) lxl = 2.7
3)3) Find the sum:Find the sum:
a) -6 + (-7)a) -6 + (-7) b) 4 + (-10)b) 4 + (-10)
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9/25/20129/25/20122.4 Subtracting Real 2.4 Subtracting Real
NumbersNumbers
GOALSubtract real numbers GOALSubtract real numbers using the subtraction ruleusing the subtraction rule
KEY WORDS: TermKEY WORDS: Term
Subtracting Real #sSubtracting Real #s
Some addition expressions can be evaluated using subtraction
ADDTION PROBLEM SUBTRACTION PROBLEM
5 + (-3) = 2 5 – 3 = 2
-2 + (-6) = -8 -2 – 6 = -8
Subtracting Real #sSubtracting Real #s
To subtract To subtract b b from from aa, add the opposite , add the opposite of b to a.of b to a.
a – b = a + (-b)EXAMPLE: 3 – 5 = 3 + (-5)
Subtracting Real #sSubtracting Real #s
EXAMPLESEXAMPLES
a. 10 – 11a. 10 – 11 b. 11 – 10b. 11 – 10
10 – 11 = 10 + (-11)
= -1
11 – 10 = 11 + (-10)
= 1
Subtracting Real #sSubtracting Real #s
Expressions with more than one Expressions with more than one subtractionsubtraction
EX: EX: 4 – (-4) - 54 – (-4) - 5
4 – (-4) – 5 = 4 + 4 + (-5)8 + (-5)3
PRACTICEPRACTICEa.4 – 5
b. 0 – (-7)
c. -2 - 8
PRACTICEPRACTICE
d. 2 – (-3) – 6
e. -3 -2 – (-5)