Use the order of operations (PEMDAS):
Parentheses, Exponents, Multiplication & Division, and then Addition & Subtraction
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1) (8 - 2) + 18 x 6
Parentheses (8 - 2)
6 + 18 x 6
Multiplication (18 x 6)
6 + 108
Addition (6 + 108)
114
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2) (15 + 29 - 4) x 4
Parentheses (15 + 29 - 4)
40 x 4
Multiplication (40 x 4)
160
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3) (13 + 5) x (13 - 5)
Parentheses (13 + 5) and (13 - 5)
18 x 8
Multiplication (18 x 8)
144
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Answers: 114, 160, 144