Answer:
w = 17
Explanation:
Isolate the variable, w. Note the equal sign, what you do to one side, you do to the other. Do the opposite of PEMDAS.
PEMDAS is the order of operations, and stands for:
Parenthesis
Exponents (& Roots)
Multiplications
Divisions
Additions
Subtractions
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First, subtract 13 from both sides of the equation:
4w + 13 (-13) = 81 (-13)
4w = 81 - 13
4w = 68
Next, divide 4 from both sides of the equation:
(4w)/4 = (68)/4
w = 68/4
w = 17
w = 17 is your answer.
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