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Algebra Difficulty 2.2 Junior Find the answer

The numbers 4x,2x3,4x34x, 2x-3, 4x-3 are three consecutive terms in an arithmetic sequence. What is the value of xx?

A number or a short expression. Spacing and $ signs are ignored.

Solution

Since 4x,2x3,4x34x, 2x-3, 4x-3 form an arithmetic sequence, then the differences between consecutive terms are equal, or (2x3)4x=(4x3)(2x3)(2x-3)-4x=(4x-3)-(2x-3). Thus, 2x3=2x-2x-3=2x or 4x=34x=-3 and so x=34x=-\frac{3}{4}.

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