Answer:
x = 36
Explanation:
Multiply both sides of the equation by the inverse of the coefficient of x.
(2/1)·(1/2)x = (2/1)·18 . . . . . . . coefficient of x is 1/2, so we multiply by 2/1
x = 36
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This "multiplicative inverse" is also called the reciprocal. It has the property that when multiplied by the coefficient of x, the result is 1, the multiplicative identity element. So, your equation becomes ...
1·x = 36
The property of the multiplicative identity element is that anything multiplied by it is that thing. So, 1x = x, and your equation becomes
x = 36
This is the solution you're looking for.