Answer: -4.5, but only if the phrase "five twice the sum . . ." means 5*2*(the sum of . . .). "five twice" is confusing, so please check the question.
Explanation:
5*2*(X + 3) = 3*(2X - 1)
10X + 15 = 6X -3
4X = -18
X = -18/4
X = - 4.5
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