Question 117562
"a number" suggests that you have an unknown number. Represent it by x.
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The sum of "a number" and 7, can therefore be represented by (x + 7). Then 3 times that is:
3(x + 7).
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"Yields the same result as" is just a fancy way of saying "equals" ... So up to this point 
you have:
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3(x + 7) = 
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Next, twice the same number is 2x and that decreased by 4 is 2x - 4. So the total algebraic
statement becomes:
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3(x + 7) = 2x - 4
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