Answer :
An equation is formed of two equal expressions. The sum of all possible values of x is 16.
What is an equation?
An equation is formed when two equal expressions are equated together with the help of an equal sign '='.
3x + 2y = 21
3x = 21 - 2y
x = (21-2y)/3
Since the value of x is needed to be positive, the value of 2y must not exceed 21. Also, the value of (21-2y) must be a multiple of two.
Now, the values of y that will satisfy the given condition in the equation are 0, 3, 6, and 9.
Further, the sum of the possible values of x are,
Sum = 7 + 5 + 3 + 1 = 16
Hence, the sum of all possible values of x is 16.
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