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If (3x)/2 +4/7 ((9x)/4-7/8)-1 = 2/7 (1+(...

If `(3x)/2 +4/7 ((9x)/4-7/8)-1 = 2/7 (1+(3x)/8)` , then x = ______.

A

`1/3`

B

`3/2 `

C

`2/3`

D

3

Text Solution

AI Generated Solution

The correct Answer is:
To solve the equation \[ \frac{3x}{2} + \frac{4}{7} \left( \frac{9x}{4} - \frac{7}{8} \right) - 1 = \frac{2}{7} \left( 1 + \frac{3x}{8} \right), \] we will follow these steps: ### Step 1: Simplify the left side of the equation Start by simplifying the left side: \[ \frac{3x}{2} + \frac{4}{7} \left( \frac{9x}{4} - \frac{7}{8} \right) - 1. \] First, distribute \(\frac{4}{7}\): \[ \frac{4}{7} \cdot \frac{9x}{4} - \frac{4}{7} \cdot \frac{7}{8}. \] This simplifies to: \[ \frac{9x}{7} - \frac{1}{2} \quad (\text{since } \frac{4 \cdot 7}{7 \cdot 8} = \frac{1}{2}). \] Now, substituting back, we have: \[ \frac{3x}{2} + \frac{9x}{7} - \frac{1}{2} - 1. \] Combine \(-\frac{1}{2} - 1\) to get \(-\frac{3}{2}\): \[ \frac{3x}{2} + \frac{9x}{7} - \frac{3}{2}. \] ### Step 2: Combine like terms Now, we need to combine the \(x\) terms. We will find a common denominator for \(\frac{3x}{2}\) and \(\frac{9x}{7}\), which is 14: \[ \frac{3x}{2} = \frac{21x}{14}, \quad \frac{9x}{7} = \frac{18x}{14}. \] So, we can rewrite the left side as: \[ \frac{21x + 18x}{14} - \frac{3}{2} = \frac{39x}{14} - \frac{3}{2}. \] Now, convert \(-\frac{3}{2}\) to have a denominator of 14: \[ -\frac{3}{2} = -\frac{21}{14}. \] Thus, the left side becomes: \[ \frac{39x - 21}{14}. \] ### Step 3: Simplify the right side of the equation Now simplify the right side: \[ \frac{2}{7} \left( 1 + \frac{3x}{8} \right) = \frac{2}{7} + \frac{6x}{56} = \frac{2}{7} + \frac{3x}{28}. \] Convert \(\frac{2}{7}\) to have a denominator of 28: \[ \frac{2}{7} = \frac{8}{28}. \] So the right side becomes: \[ \frac{8 + 3x}{28}. \] ### Step 4: Set the two sides equal Now we have: \[ \frac{39x - 21}{14} = \frac{8 + 3x}{28}. \] Cross-multiply to eliminate the fractions: \[ 28(39x - 21) = 14(8 + 3x). \] ### Step 5: Expand and simplify Expanding both sides gives: \[ 1092x - 588 = 112 + 42x. \] Now, move all \(x\) terms to one side and constant terms to the other: \[ 1092x - 42x = 112 + 588. \] This simplifies to: \[ 1050x = 700. \] ### Step 6: Solve for \(x\) Divide both sides by 1050: \[ x = \frac{700}{1050}. \] Simplifying this fraction gives: \[ x = \frac{2}{3}. \] ### Final Answer Thus, the value of \(x\) is \[ \boxed{\frac{2}{3}}. \]
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